# Learn How to Crochet a Beanie that Fits!

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Learn how to crochet a beanie* that fits!* This post includes measurements for the average head sizes and crochet hat sizes for preemies to adults, instructions on how to measure your head size properly, 3 different measurements for hat heights different hat styles for babies to adults, the flat circle diameter measurements for each of the hat sizes included, instructions on how to increase for each round of your hat pattern and the starting number of stitches you need for 4 types of crochet stitches. I have also included information about how to determine how many stitches you need for your hat circumference based on stitch pattern gauge.

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## Average Head Sizes and Hat Sizes

For these average head and hat sizes I have allowed 2 inches of negative ease. We allow negative ease to take into consideration how much a hat is going to stretch from being worn. Some yarns don’t stretch very much, like cotton yarns, so if you are using a fiber that doesn’t stretch you will want to allow less negative ease. I recommend increasing the hat size by 1-inch for each size listed below, if you use cotton yarns.

**It is also important to note, if you have a head to measure, measure it!**

### How to Measure Your Head Size

### Measuring the circumference

*If you do not have a measuring tape, cut a length of string approximately 30 inches long.*

*Take your string (or measuring tape) and place the one end approximately 1/8″ above the top of your ear.**Wrap the string firmly (but not tightly) around your head, across the middle of your forehead and back to your starting point at your ear.**Pinch the end of the string where it meets the beginning point (don’t let go!) and remove the string from your head.*- Place the string on a flat surface and either continue to hold the spot where you are pinching, or use a pen to mark that spot so you can let it go. Then take your ruler and measure the length of the string.

This will give you the circumference of your head. When you are making a hat you will want the hat to be slightly *smaller* than your head in order for it to fit properly. Depending on the type of material you are working with, the amount smaller will vary because some materials do not stretch very well.

For example, cotton doesn’t stretch very well and once it has stretched it rarely goes back to its original size. You will need to make a hat closer to your head size (approximately 1 inch smaller) if you are working with cotton yarns.

I have included the measurements I use below when I am working with Medium Weight [4] and DK Weight [3] acrylic yarns.

I hope you find these measurements helpful.

### Average Head and Hat Circumferences

**Preemie****Head Size:** 12 inches**Hat Size:** 10 inches

**Newborn****Head Size:** 14 inches**Hat Size:** 12 inches

**0-3 months****Head Size:** 16 inches**Hat Size:** 14 inches

**3-6 months****Head Size:** 17 inches**Hat Size:** 15 inches

**6-12 months****Head Size:** 18 inches**Hat Size:** 16 inches

**1-3 years****Head Size:** 19 inches**Hat Size:** 17 inches

**3-5 years****Head Size:** 20 inches**Hat Size:** 18 inches

**6-10 years****Head Size:** 21 inches**Hat Size:** 19 inches

**Adult Small (Teen)****Head Size:** 22 inches**Hat Size:** 20 inches

**Adult Medium****Head Size:** 23 inches**Hat Size:** 21 inches

**Adult Large****Head Size:** 24 inches**Hat Size:** 22 inches

### Flat Circle Diameter

For those of you who want to make your hats in the round, you will also be needing your flat circle diameter measurement. The flat circle diameter is calculated by taking the hat circumference and dividing it by 3.14 (pi). This gives you the diameter your circle needs to reach in order for the finished hat to be equal to the hat circumference you have chosen.

**For example:**

**Preemie**

(hat size 10 inches circumference)

10 / 3.14 = 3.18

10 inches divided by 3.14 (pi) equals 3.18 inches diameter

**Here are the flat circle diameters for the hat sizes I gave you above:**

**Preemie** 3.18 inches diameter**Newborn** 3.82 inches diameter**0-3 months** 4.45 inches diameter**3-6 months** 4.77 inches diameter**6-12 months** 5.09 inches diameter**1-3 years** 5.41 inches diameter**3-5 years** 5.73 inches diameter**6-10 years** 6.05 inches diameter**adult small (teen)** 6.36 inches diameter**adult medium** 6.68 inches diameter**adult large** 7 inches diameter

**When you crochet hats in the round (or in continuous rounds) you normally begin with one of these 3 methods:**

- a Magic Ring
- a Double Magic Ring
- a ch-3 and then a slip stitch to the first ch, to create a ring

Depending on the height of the stitch you use, it will take more stitches to make it around for the first round of your hat and for the fabric to lay flat.

**The recommended number of stitches to begin your round with are as follows:**

**Single Crochet:** start with 6 stitches**Half Double Crochet:** start with 8 stitches**Double Crochet:** start with 12 stitches**Treble Crochet (triple crochet):** start with 18 stitches

This also means that when you are increasing to reach the circumference of the hat you have chosen, you will be increasing by that same number of stitches on each round. You will work these increases until you reach the **flat circle diameter** measurement indicated for your hat circumference and then you begin crocheting without increases until you reach the hat height you want.

During your increase rounds, when you are crocheting your hat, if the **flat circle** begins to cup up towards you this means there aren’t enough stitches for your yarn and hook to work with. You will need to increase your starting number of stitches. If you were using 8, try using 10.

If the flat circle becomes all wavy and it ruffles away from you, you have too many stitches for the yarn and hook you are using. Try using less stitches.

After you have reached the flat circle diameter measurement and you are working the same number of stitches for each round (working even) your hat will begin to cup up toward you. This is supposed to happen and is how the hat shapes itself. If you see your hat start to get wavy and ruffled then you may have increases in the rounds you were not supposed to be increasing in. Double check your stitch count.

The above example explains how to increase your stitches on each round until you reach your flat circle diameter. If you wanted to continue working in a circle you could simply change the number in pink on each additional round. So after Round 6 you would work the following for Round 7.

**Round 7:** (2 dc in next st, 1 dc in each of the next 5 sts) repeat around. [84]

For the above example you can see that we began with 12 stitches and each round increases by 12 stitches. While we are adding these additional stitches on each round it is called ‘increasing’ so these are our Increase rounds.

Once you reach your flat circle diameter, you stop increasing and you continue to work the same number of stitches in every round until you reach the desired hat height. These rounds we are working ‘even’, or without increases.

Once you get used to working in the round and making increases, you can stagger your increases around the round instead of working them in the same spot each time. By staggering those increase stitches you will have a smoother hat and it will seem rounder and the increases will not be as noticeable.

This technique is often used in amigurumi and you will even see instructions written for a round that say increase 9 stitches on this round. The reason they don’t say ‘where’ to work them is because they want you to stagger them around the round. It will make the finished project rounder and those increases less noticeable.

### Crochet Hat Heights

There are many different hat heights you can work for your crochet patterns. These are the 3 different heights I use most frequently. If you are making Earflap hats I recommend working to the mid ear hat height before beginning the earflap rounds. If you are making a hat with a folded brim a slouch hat height often works well. I have included the 3 lengths I use the most, by head size below.

**Preemie****Mid Ear Hat Height:** 4 inches**Base of Ear Hat Height:** 4.5 inches**Slouch Hat Height:** 5 inches

**Newborn****Mid Ear Hat Height:** 4.5 inches**Base of Ear Hat Height:** 5 inches**Slouch Hat Height:** 5.5 inches

**0-3 months****Mid Ear Hat Height:** 5.25 inches**Base of Ear Hat Height:** 6 inches**Slouch Hat Height:** 6.25 inches

**3-6 months****Mid Ear Hat Height:** 5.5 inches**Base of Ear Hat Height:** 6.25 inches**Slouch Hat Height:** 6.75 inches

**6-12 months****Mid Ear Hat Height:** 5.75 inches**Base of Ear Hat Height:** 6.75 inches**Slouch Hat Height:** 7.25 inches

**1-3 years****Mid Ear Hat Height:** 6.25 inches**Base of Ear Hat Height:** 7 inches**Slouch Hat Height:** 7.50 inches

**3-5 years****Mid Ear Hat Height:** 6.5 inches**Base of Ear Hat Height:** 7.5 inches**Slouch Hat Height:** 8 inches

**6-10 years****Mid Ear Hat Height:** 7 inches**Base of Ear Hat Height:** 8 inches**Slouch Hat Height:** 9 inches

**adult small (teen)****Mid Ear Hat Height:** 7.25 inches**Base of Ear Hat Height:** 8.25 inches**Slouch Hat Height:** 10 inches

**adult medium ****Mid Ear Hat Height:** 7.5 inches**Base of Ear Hat Height:** 8.75 inches**Slouch Hat Height:** 11 inches

**adult large ****Mid Ear Hat Height:** 7.75 inches**Base of Ear Hat Height:** 9 inches**Slouch Hat Height:** 12 inches

If you want to work a *specific stitch pattern* and you have the gauge for the stitch pattern, you can simply take the gauge and **multiply it by the size hat** you want to make. This will give you the exact number of stitches you will need for your hat circumference. I’ve included an example below so you can see what I mean.

This is the method I use when I design my patterns. I really want your hats to fit correctly. I know that when we work to a specific flat circle diameter and we do not take into consideration the gauge being used, the hat can end up being much too large for someone’s head.

So first I work a sample hat using the stitch pattern I want to use with a flat circle diameter measurement. I work enough of the hat to find out what my gauge is for both stitches per inch and rounds per inch. I work the sample in the round because I know gauge fluctuates between projects worked in rows and worked in rounds. It has something to do with how we hold our work when we crochet. Often when we crochet in rounds we have a bit tighter gauge.

Once I have my gauge, I calculate the stitches I need for each size in my pattern for the hats I want to offer and then I work up my samples. I create the hat pattern based on a specific stitch number, rather than to the flat circle diameter measurement.

Sometimes for my last round, to reach my flat circle diameter measurement, I only increase 6 out of the 12 stitches I could increase by. This is because with those 6 extra stitches I have already reached the number of stitches I needed to make the hat the right circumference.

If I increased for that entire round I could potentially increase by 6 stitches too many. If you are working with *3 stitches per inch* this would mean my finished hat would be *2 full inches too large*.

It could still fit at first because I normally allow for 2 inches of negative ease, but the hat would end up being the exact same size as the head it was meant for. After being taken on and off a few times, the hat would stretch and it would be much too large. This is why I feel gauge is important for hat designs and why my final round of increases in a pattern does not always follow the formula I gave you above.

I hope this post has been helpful to those of you who want to start designing your own hats. Feel free to leave me questions in the comments, if you have them.

Thank you so much for your quick respond. I will do that for sure. Great tip now I will have beanies that fits. Your the best

Hi Christine, Sometimes for smaller stitches like single crochet (that have shorter heights) you may have to work a round even after each increase round. So crochet the same number of stitches for one round and then work the next increase round) to help the hat reach the diameter. I haven’t experienced this issue with hdc stitches before but if you are mixing the stitches with sc stitches for the hat you may need to work a round using both (the stitch pattern you are using) in between each of the increase rounds.

Thank you for this info. I have a problem though. I use the correct size hook for the pattern. I crochet loose and can’t go up a size. My sc and hdc don’t get me to the correct diameter. It always comes out smaller than what it is suppose to be. What can I do to rectify it please? Use the correct yarn as well. Any advice will be appreciated.

Hi Rhonda sorry for taking so long to reply. I did not see your response. The yarn only recommends knitting needle sizes 4 (4-6 US). I’m now using stylecraft which recommends 5.5mm hook but I am still having problems. My gauge is 3st per inch as you say it should be, and I can now reach the correct flat circle diameter. However my hat has still ended up being 3” too big and a funny shape and uneven when tied off. Am I correct in thinking that you work the rounds continuously without joining at the end of each round? Sorry for being such a pain I just can’t figure out where I’m going wrong!

Hi Cherelle, So you are trying to make a hat that is 14 inches in circumference, for a 0-3 months head size of 16 inches. Generally Medium Weight Yarn is about 3 stitches per inch with a 5.5 mm hook. Have you tried upping your hook size? Fabric that is crocheted using a smaller hook than is needed tends to be super firm and unyielding. Beyond this, the Flat Circle Diameter is an approximate number so if you are off by .1 or .2 of an inch this is ok and you can proceed to make the rest of the hat. You will need to maintain the same number of stitches per inch or the hat will grow in size and be too large once it reaches the hat height recommended for this size.

I’m a bit concerned that your hook size is not quite right for the yarn you are using. We usually use a 4.5 or 4 mm hook with Worsted/Medium Weight Yarn when we are making amigurumi with very tight stitches. Did the yarn recommend a 4 mm hook on the label?

Thank you for checking,

R

Thanks for responding. I’m also using medium weight. I’ve realised since my first comment on august that my gauge is 4 st per inch. I’ve been trying all day to do 4.45inch diameter. I began with 4mm hook and 10 and 12 stitches to reach 56. That was too big. I’ve tried again with a 4.5mm hook and with 12dc to begin and it’s 4.6inches. The circle is fully flat. I’m so confused!

Hi Cherelle, Depending upon the yarn weight you are using you may need to begin with more or less stitches per round in order to reach the flat circle diameter you need. The examples I was working with were for Medium Weight Yarn. Does the flat circle lay perfectly flat, or is it already trying to shape (curving in) or is it wavy (seems like it is floppy)? I’m thinking it has been trying to cup /shape itself and that would mean you need to increase the starting number of stitches you are working with. Did you do a gauge swatch in advance? To see how many stitches you needed to have for the final hat circumference?

Thanks Rhonda.

When I reach my desire amount of stitches the flat circle ends up much larger than the diameter on the chart. What could I be doing wrong?

Hi Cherelle, I would work *2 dc in the next st, 1 dc in each of the next 23 sts** 4 times. So yes increase once time every 24 stitches. Best wishes, Rhondda

Hi, my dc gauge is 5 st per inch which means I would need 100 st for a 20” hat. If I increase by 12 each round, after 8 rounds I have 96 stitches. How do I increase by the last 4 sts? Would it be An increase in every 24th stitch? (96/4)? Thanks

It sounds like you need a smaller hat size for your head – or a ‘shorter’ hat, less rows/rounds worked for the stitch pattern. You can thread a piece of narrow elastic through the brim round of stitches to make it a bit tighter for hats that are already complete. I tend to prefer short slouch hats that are more like a beanie than a slouch with the ribbed brim and top-down hats. Sometimes heavier hats don’t stay put as well as others and with wear can stretch out and slide down lower on the forehead (or pull off at the back because of the weight). Hats should be smaller than the head because taking them on and off makes them stretch and some yarns don’t recover to go back to the way they were when we started. That’s one reason I never let anyone else wear my hat because if their head is larger the hat never fits me again because it has become stretched out of shape too far. I hope the elastic trick works for you! Best wishes, Rhondda

Every hat I have slides right down over my eyes. Any tips to stop this?

You are most welcome Christine 🙂 I glad it was helpful. Have a lovely week, Rhondda

This has to be the most detailed, informative and helpful post of crocheting hats that I’ve ever come across. And I’ve been crocheting a very long time!!

Thank you for all the time and effort it took to our this together, and for generously sharing your talent!

Yes, there are a couple reasons this might be happening. It might be because there are too many stitches in the last round where the crown reaches the diameter measurement. When I write my patterns I write for specific circumferences rather than the diameter measurement because of this issue – a lot of people don’t realize how much a couple stitches will add to the finished size of a hat but it can be the difference between a hat fitting a toddler or an adult.

Diameter is a great starting point and there are many tools and templates that only use this as a factor but they will not always work out for some of the head sizes (depending on the yarn you are using).

For example, we know that 3 stitches can add an extra inch in size to a hat so when we simply increase until we reach the flat circle diameter (not taking into account any other maths) then that last round could increase between 1 and 12 stitches (if you are working with 12 stitches in a round).

My recommendation is to check the size head you want to make a hat for then check how many stitches you have in an inch. Usually when I am working with a Medium Weight Yarn that would be 3 (sometimes 4). So if you want a hat to fit a 20 inch head size and you are using Medium Weight Yarn, remove 2 inches for negative ease (we want the hat to stretch to fit the head – not to be the same size as the head – the action of putting it on and off repetitively will stretch the hat and it will become too large if it starts out the same size as the head). So go with 18 inches for the hat size. Then take your 3 stitches per inch x 18 inches to get the number of stitches you need to have in that last round to reach the diameter. So about 54 stitches will be needed.

If we were following the diameter measurement without taking into account stitches per inch this is what would happen:

R1: 12 dc

R2: (2 dc in the first st, 1 dc in the next st)x 12 = 24 dc

R3: (2 dc in the first st, 1 dc in the next 2 sts)x 12 = 36 dc

R4: (2 dc in the first st, 1 dc in the next 3 sts)x 12 = 48 dc

R5: (2 dc in the first st, 1 dc in the next 4 sts)x 12 = 60 dc

Chances are your flat circle diameter will be reached around Round 5 of the hat.

If you simply work those regular increases every 12 stitches when you are done R5 you have 60 stitches.

Instead of the 54 that you need for the 18 inch hat.If you take that extra 6 stitches and apply the 3 stitches per inch gauge that gives you an extra 2 inches of hat. So simply following flat circle diameter will not always work out.You would need this for R5: (2 dc in the first st, 1 dc in the next 7 sts)x 6 = 54

Since we only need to increase 6 more stitches to have a finished hat that is 18 inches circumference.

So my recommendation would be after you have worked a few rounds of the hat using the flat circle diameter method, measure approximately how many stitches you have in an inch. Then decide what hat size you want and multiple that finished hat circumference by the stitches / inch to see how many stitches you need in the hat. Then adjust that last round to only add the number of stitches necessary. I hope this makes sense.

Once you have one hat done with that yarn and hook, all the other hats will be easy to calculate because the gauge will be the same 🙂 so all you need to do is apply the math for stitches x circumferenc for a closer idea of what finished hat size you need.

The only other reason the hat is larger than expected if you do have the same number of stitches would be if you gauge changes after you stop increasing (adding extra stitches). It is common that when we start working repeat rounds without increases that our tension/gauge relaxes or tightens and doesn’t stay consistent with when we were counting and really paying attention to what we were doing. That can make more stitches per inch in the final rounds than near the beginning. This usually only accounts for an inch of increase or decrease in size though for hats since they are smaller projects.

Let me know if you have any other questions, I’m happy to help where I can. I am sorry this is such a long answer 🙂

Best, Rhondda

This is so helpful to have all in one place. My big problem with hats is that I can check my gauge and increase until the crown reaches the recommended diameter, but once I start just increasing the body of the hat my circumference still gets wider and wider even though I’m not increasing stitches (and I double check to ensure I’m not doing so accidentally). This means that I often end up with 2 inches wider circumference than should be based on when I stop my crown no matter how tightly I try to crochet. Is this something you are familiar with?

You are most welcome Sharon!

I am new to crocheting and this is super helpful. I made one had that was a little bit too big but now I know where I went wrong. Very useful information. Thank you for sharing.

Hi Cheryl, I use the hook size specified *usually* on the yarn label 🙂 Thank you, Rhondda

Love the charts. Thanks for posting them. I dont see a hook size tho?

Hi Lynn, You are very welcome 🙂 I usually make my triangles in rows to be honest – unless you mean like a granny triangle? I think I have one of those on here somewhere – I used it to make Christmas Trees – so the post might be under Christmas Trees. I’m happy I was at least able to help with the hats! Have a lovely week, Rhondda

Rhonda, I just started crocheting a few months ago, and I can’t express enough the value of this tutorial! Thank you, thank you, thank you! I have used the concepts over and over and my products are very professional looking because of the information you provided. You are awesome!

I am going to search your site now and see if I can find the same math concepts for crocheting rectangles in the round.

Hi Kristin, If the stitches are shorter like hdc or sc you can finish off with an invisible join and weave in your ends. Once you wear the hat and stretch it to fit the head it is very difficult to see the small angle of the last stitch that wasn’t the same height as the others.

If you are using taller stitches you can work staggered stitches to reach a closer height between the last and first stitches of the rounds. So if you are using double crochet, remove the last 2 dc stitches an in their places work 1 hdc, and 1 sc then do an invisible join to finish the hat.

You can see how to use the invisible join here: https://oombawkadesigncrochet.com/invisible-join-technique/ there is also a link to the spot in one of my video tutorials that shows you how to do the invisible join.

Hope this helps! Rhondda

I forgot to add more detail. I did stop increasing after my flat round reached my needed diameter and started working on the hat height. However, instead of having a point where I’d normally join the end of the row with the beginning with a slip stitch then create a chain to start a new row, the hat continued in a spiral. When I reached my desired height, I had a drop off where the end of my row rose above the beginning. How do I finish the hat this way?

Hi Pegi, I don’t – I actually haven’t been brave enough to try felting yet! But I did find this resource from Mikey at the Crochet Crowd which may be of some help: https://web.archive.org/web/20210417075150/https://thecrochetcrowd.com/calculator-crochet-stitch-counts-for-felt-shrinkage/ All the best, Rhondda

Your site is great! I’m wondering if you have some kind of formula or chart that tells how to crochet a simple beanie big enough to felt down to a man’s or woman’s size. I have had no luck finding something like this online.

Hi Kristin, When you start the hat it will work flat while you are adding your increases (extra stitches in the rounds). After you stop adding extra stitches the hat begins to take shape into a cupped shape (like a bowl) which will fit your head once you reach the right height for your hat. If you have stopped adding stitches and are already working in rounds (without extra stitches being added) and have worked 4 rounds (approximately) without any extra stitches, then you may have relaxed your gauge and changed the number of stitches you are working in each inch. Another issue could be if you are changing the stitch pattern. Some stitch patterns will have more or fewer stitches within every inch – so if you are making a hat with a stitch pattern, the hat may not shape up the way you expect. You would need to check your gauge for the stitch pattern you are planning to work, not the regular single crochet or half double crochet stitches you used for the increase rounds. I hope this makes sense? Let me know if you have questions! Best, Rhondda

When creating the top of the hat and working my increases, the rounds just continued in a spiral with no end. Is that normal?

I really enjoyed the information in this post about making crochet hats! I never knew that cotton yarn does not have much stretch and that hats should be made smaller than the head. This makes finding all the information to make a hat in one place!

I Chelle, You can follow this pattern if you’d like for Santa Hats – I have one written for all sizes: https://oombawkadesigncrochet.com/santa-hats-for-everyone-free-crochet-pattern/ My post explains how to make hats using pi (3.14) – it includes the basic hat and head sizes for all ages too. If you follow the post it will walk you through it step by step – it includes both the measurements, the math and the hat heights. I’ve never heard of the fold in half and measure and multiply by pi method. For hats you start with the size head you want to make your hat for and then calculate the number of stitches you will need to reach that measurement. Read my post and then if you have any specific questions, please let me know. I’d be happy to help, Rhondda

How would this work for an elf/pixie/santa hat, with a long tail. I have been crocheting 20+ years and I am struggling with this for some reason. I have seen where some say when you get to where you want to stop increasing, fold hat in 1/2, and measure, than multiply by pie (3.14) and that will be around the finished circumference, but it doesn’t work out. I don’t have the specific head measurements just ages of children who will be wearing them. Am I missing something? Thanks in advance 💜

wow, where has this post been all my life?? Best explanation for making beanies from age to size to increase’s….happy happy, where’s my crochet hook?

Hi CP it would really depend on the type of yarn you are using too – some stretch more than others – and since there is no ‘top’ to the sunhat (it is open) you wouldn’t want it to be too tall and stretchy, with the top opening, or it would just slide down the head with the weight of the brim. If you mean a ponytail sunhat – that has the small opening at the top for the ponytail to be pulled through, I’d start with an elastic band and work your stitches around that before working to the number of stitches you need for the circumference of the head. If you want a slightly bigger opening and the assurance that it won’t slide off the head I’d be temped to use a couple elastic bands to form the top ring that you work your stitches around. I hope that makes sense! Best of luck! Rhondda

Hi.

I am a newbies. My friend has requested me to do an open top sun hat. Do you have any recommendation how to start? This is what i think. Do up the chain stitches and the length will be the circumference. I am stuck after that as i think we need to gradual decrease n then increase before i reach the brim.

Thank you so much for this post! I am a VERY beginner crocheter. I made my adult son a hat — it came out just perfect…for a newborn! You made everything easily understandable. I am now ready to begin working on a new hat and this time it will fit!

You are very welcome! Have fun 🙂 Rhondda

Wow! I just found information I have never known. I can make custom hats now!! Thank you for shearing.

Lisa

Hi Sheen, the size of the hat would be 20 inches in circumference if you have maintained 6 stitches per inch. If the yarn you used has a lot of stretch – for example if you make a small sample using the stitch you want to use for the project and pull to stretch it – if it stretches more than 2 inches easily then you may need to decrease the number of stitches to compensate. Another reason you may have a bulky look is if you increased to the 120 too quickly and your flat circle is not flat when you put it on a flat surface. Hope this helps a bit! Rhondda

Hi, excellent post. I’ve been reading my way through it carefully so that i now have a better understanding of crochet hats. I recently made a hat using sock weight yarn for a small adult teen (circum. 20 inches on your chart) i had 18dhc stitches per 3 inches making 120 stitches in circumference but it’s come out very baggy. Just wondering if the thinness of the yarn affects the eventual fit? Thanks

Hi Kim, I think my herringbone hdc are slightly taller than a regular hdc but they tend to be the same width (stitches per inch way). Hope this helps, Rhondda

Hello Rhondda.

This is the perfect guide for hat sizing. Flat circle diameter method actually never worked for me.. Then I also used gauge method. It always results in perfect fitting hat.

Would a herringbone half double crochet measure the same as a hd crochet?

This is by far the absolute BEST description on hat measurements, and I have read tons! You have clarified so much, especially the part about the adjustment when using cotton! They always turned out too small…thanks to your excellently detailed description, my hats will turn out so much better! Thank you for being so generous in sharing! That’s a sign of a good person!!!

Hi Nancy, Yes 🙂 .32 is approximately 1/3 of an inch. 1/4 of in inch would be .25, 1/2 an inch is .5 and 3/4 of an inch is .75.

So the 7.32 is 7 and 1/3 inches.

Gauge is determined by 2 factors, the height and width of the stitches. Usually a pattern will indicate how many rows or rounds per inch and how many stitches per inch.

For the equation you are checking for the stitches per inch. So the width of the stitch, not the height.

For your hubby’s hat you would need to know what size his head circumference is and then do a gauge swatch to find out how many stitches per inch you have. Once you know how many stitches you have then you can decide how many stitches you will need for the hat size. So if his head is 25 inches, you should aim to make a hat between 23-24 inches circumference.

I hope this helps. Feel free to ask me more questions if you need to 🙂 Best wishes, Rhondda

I’m loving all this help with the math, as I am not a math person at all. I’ve made several hats, but most (not all, but most) simply don’t fit as pleasingly as I’d like. Thus, I figured that I neeeeed to go back to the BASICS and learn from the beginning. You’re helping me do this. (THANK YOU!)

But I do have a question. It’s a basic question & so may seem utterly lame, but when you talk about GAUGE, are you referring to how TALL or how WIDE my stitches are? (Or is it both?) B/c I’m can’t think how 3 Dcs can = 3″ wide….not unless I’m using uber bulky yarn.

Also, my hubby needs an Adult XL size, so I was taking a wild stab that it would be 23 stitches in the magic circle. But when I got to the FLAT CIRCLE DIAMETER, I did the pi division (the calculator did it), and got 7.32″. What is a .32 of an inch? Do I just sorta round it to 1/3 of that inch? (Like I said, I’m not a math person.)

Hi Gill, The measurements are the same. When you use heavier weight yarns there will be more stretch (elasticity) in the yarn though so you will need to allow a little bit more negative ease. For example I generally allow 2 inches of stretch for my hats so if someone has a 20 inch head size I aim for an 18 inch hat size because medium weight yarn normally stretches (unless you are using a super tight stitch pattern) 2 inches. When using Aran weight and bulkier weight yarns it can stretch significantly more. I usually do a small swatch to see how much stretch I can get on a square and then change my finished hat size according to this. I hope this makes sense 🙂 I’m happy you found the post helpful 🙂 All the best, Rhondda

It seems my first comment never posted! Thank you so much for doing all the maths. I’ve managed to knit an adult man’s hat using these tips and guidance. It curled, I altered the stitch count and presto flat circle. In worsted weight yarn. Thank you and Happy Christmas.

Thank you for this blog post explaining hats. If using worsted weight/Aran (5) are the measurements the same? i.e. for a man’s hat are we still aiming for 7″ diameter?

The tips about curl/ruffle were extremely useful!

Hi Michelle, I’m happy that the information I shared has helped!! Thank you for letting me know 🙂 Have a lovely week, Rhondda

I am working on a hat from a free pattern. I remembered there were places that helped with things like the measurements of your circle and went on a search. I found MORE than I needed and also received the answer to why the circle was buckling a bit. She starts with 12 hdc in the circle! Frogged back, made 8 and voila! – no more curl. It just added one extra row but made a world of difference. So not only did you help me figure out my diameter, hat height and hat circumference – you solved a problem I really didn’t realize I had. Wonderful page and I will be sure to share about it.

Very welcome 🙂 I’m happy to help! Rhondda

Wow! Thank you so much for this. Sooooo helpful.

You are very welcome Sangeetha 🙂 Have fun! and if you have any questions, please just let me know. All the best, Rhondda

Thank you so much for this wonderful post. I always made hats that fit me or my husband. Now I can explore other sizes too.

Have a lovely day. Regards from India 🙂

You are so welcome 🙂 Let me know if you have any questions – it might take me a bit of time to respond but I will respond as soon as I can! Have a lovely weekend, Rhondda

I was stressing out until I remembered seeing your Awesome Hats on Pinterest. Thank You so Much ! You have such a Generous Big Heart of Love! God Bless You!

You are very welcome Darcy 🙂 Let me know if you have questions – it might take me a bit of time to get back to you (I have 2 children) but I will try my best to help 🙂 Have a lovely weekend, Rhondda

Thank you for this post. It’s fantastic. Now I can make any size hat!! I’m excited.