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Why Size Matters in Crocheting and Knitting

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We’ve all heard it: Size matters.  And you know what? It’s true, friend. Hook size matters!

Why Hook Size Matters in Crocheting and Knitting

Size DOES matter, when it comes to crocheting and knitting, that is.  In fact, it makes all the difference in the world. Both your hook size matters (or needle size in knitting) and your yarn size matters when it comes to how uniform and professional your items turn out.

Why Hook Size Matters in Crocheting and Knitting

Hook size matters

There are all different sizes of crochet hooks.  Some are so itty bitty you can literally crochet with sewing thread. Others are so large you could almost use them for a walking stick. For those bigguns, you might as well use your arm.

Hook sizes are measured either by their letter in the alphabet, or by their size in millimeters starting with the smallest.  I personally use the letters, but that also depends on where in the world you live.

Where in the World, is Carmen Sandiego? Hee hee!

In Europe, I understand that millimeters are used more often, while here in the United States we tend to use the alphabet. Same size technically, and the gist is the same just whatever suits your fancy.

As you can imagine, the size of your yarn makes a difference in which hook you’ll want to use as well.  If you have a very large yarn, you’ll need a very large hook.  A very small yarn? You’ll need a very small hook (unless you’re wanting it to have a loose, open and airy weave).

Yarn Size Matters

There are six main sizes of yarn.

How Hook Size Matters in Crocheting and Knitting

Starting with a size 1 which is very thin, to a 2 which is a little bit thicker, then a 3 and 4 of “worsted weight” yarn. Size 4 is the most popular yarn size.  This is the “average” thickness of yarn you’ll find when you visit the yarn store, and what a good percentage of patterns use.  Size 5 starts to get a little thicker (considered bulky) and size 6 is known as super bulky.

Does Hook Size Matter in Crocheting and Knitting? YES!

The bigger the yarn, the larger the hook size you’ll need to use (and the larger the finished product will be as well).  In the photo below, I used the exact same pattern with the exact same yarn. Same number of rows, same number of stitches.  Exactly the same.  The only difference? Hook size!

Why Hook Size Matters in Crochet

The first (smallest) was made with a D (3.25 MM), the next was made with a G (4.0 MM) hook, the next size up was made with an H (5.0 MM) hook and the largest was made with an I (5.5 MM) hook. Isn’t that interesting?

If you are wondering why I am making so many hats in these sizes, they are for donation to my local NICU.  I have the pattern listed here on Heart Hook Home, and if you’d care to join me in my donation effort (or if you want to experiment with hook size) these little hats work up in about 10-15 minutes.  Easy peasy, and a great way to understand both tension and why hook size matters.


More crochet tips:

Use Industrial Clips for Yarn Bobbins in Crochet and Knitting
Finger Burn? You Need a Finger Cuff for Crochet
9 Tips for Traveling with Crochet
The Difference Between Knitting and Crocheting & Master Your Tension
How to Soften Economical or Scratchy Yarn
16 Ways to Save at Michaels

Comments

  1. Maddi says

    hi! i’m making a hat that calls for a 6mm hook, but the biggest i have is 5.5mm. do you think there will be too big a difference? is there any way i could adapt the pattern so it would turn out the same? thanks!
    Reply

  2. Sandy says

    Hi, I’m planning on making a men’s scarf and the yarn is calling for a 9mm hook, but I only have 8mm. Will that make a huge difference? Oh is it best for me to run out and seriously get a 9mm hook? I am a beginner at this. Thank you
    Reply

    • Heart Hook Home says

      Your scarf will probably turn out a bit smaller with the 8mm, so if you don't mind that, then go ahead! Or, if possible, you could add a few stitches and rows to get the bigger size. Hope this helps!
      Reply

    • Heart Hook Home says

      You can...but the stitches might be real tight and stiff. But, if that is what you trying to achieve (like in amigurumi) go for it!
      Reply

  5. Ronnie says

    Hi there! New to crocheting. Just making a baby blanket for my sister’s unborn child and the yarn I’m using suggests using an M hook. I live very rural and cannot run to town to pick up the correct size, but I have a size bigger and a size smaller. Which size would you use in my shoes? Thanks in advance!!
    Reply

  6. Danielle says

    I want to get the pattern for a Amigurumi hippo, however, the finished product is less than a foot long. If I used a bigger crochet hook and a thicker yarn, will it maintain its shape while making it bigger? It's calling for a 3 mm hook and 5 ply yarn, 125 metres, 50 g. I would use a 4.5 mm hook and medium weight, 260 meters, 127 g. yarn.
    Reply

  7. Lucy Gladdy says

    Hi everyone, I'm super new to crocheting, I'm trying to follow the Llama-No-Drama pattern (I know its quite complex but it's just so adorable), the pattern says to use Aran yarn so I got some and on the bac on the yarn, it says to use 5mm hooks. The pattern says to use a 3.75mm hook but I only have a 3mm, 3.5mm, 4mm, and 5mm. I've tried to start the pattern multiple times which different hooks or different tensions but it never looks like the youtube guide I'm following and I thought it might be because of the yarn/hook size? Which should I hook should I use?
    Reply

    • Heart Hook Home says

      Hi Lucy! First off, welcome to the addicting hobby of crochet! I hope you love it as much as I do! As for your project, that pattern will use a hook size smaller than the yarn recommended so the stitches will be nice and tight...and so the stuffing won't be falling out of your llama. I would probably use the 3.5mm or 4mm hook. It shouldn't make a huge difference in your finished project. Hope this helps!
      Reply

    • Heart Hook Home says

      Oh no!! You would probably be okay to use the bigger hook, however your project might grow a tad, but if you try to tighten your tension the growth (if any) would be less noticeable. Hope this helps!
      Reply

  10. Helen Buddenbohm says

    Thank you for the tutorial on why needle size is important. It was nice to see what size the different needles looked like in the hats you made. Very informable! Keep up the good work.
    Reply

  11. Lisa says

    I am very new to crocheting. I am in the middle of my first afghan and I lost my hook! I think it was a 4, but I am not sure. My husband went out to get me a new one and came back with a 4.25. Will this make a noticeable difference if i continue with the new hook? I don't want it to look bad as it is for a very special little girl.
    Reply

  13. Sandy says

    I also am crocheting for my local NICU. I had a granddaughter than was in there for the first 30 days of her life. She's a adorable little 3 year old now. So I have time and yarn and decided in between any orders I might get that I would make these little hats. Very rewarding!
    Reply

    • Betty LaVigne says

      I am making a throw and pattern uses a 12mm hook , can I substitute a 19mm for this throw? Yarn I am using is Bernal blanket yarn! Thanks for your help.....Betty
      Reply

      • Heart Hook Home says

        Hi Betty! If you are also using a larger yarn than is used in the pattern, then you would probably be okay using the bigger hook...keep in mind that the blanket will turn out much larger.
        Reply

  14. Suzan says

    Hi Ashlea, I'm Suzan, the gran from Gauteng, South Africa. New comer to your blog and liking it already. So many abandoned children heee who need help and I will tap in for advice often I expect.
    Reply

  16. Jenny says

    Hi, So I have a pattern that calls for a 5-bulky yarn that has been discontinued...can I use a 6-super bulky and use a smaller hook? I'm kind of new to this... Thanks! Jenny
    Reply

    • Heart Hook Home says

      Hi Jenny! If the pattern has a gauge swatch, I would definitely do that and try to make your gauge match that of the designers. Hope this helps!
      Reply

  18. Amanda says

    Seems like most yarns I would like to use for scarves and even blankets are thicker and suggest using 9mm hook...yet when I went to look for a set of hooks like the ones you show in your pictures...(the clover takumi soft grip)...they don't come in the bigger sizes. Why is that? I haven't crocheted in years and have recently started back and wanted to buy some really good hooks but noticed these are all on the smaller side. Any suggestions...?
    Reply

  20. Eunice Maris says

    Not all crochet threads coming from other countries give the size of the thread. If a site states a recommended hook size 1-3mm, what is that thread size? I am looking for a rayon mix thread in various colors, size 4 or approximate. Do you know of a source? Many thanks, Eunice Maris
    Reply

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