Crochet hook size

[Borisrules]

Newbie here so please don't laugh....
Just doing a cute wavey striped beanie for myself...trouble is it won't even fit on my 2 year olds head. Stitch count is corrrect. But just noticed hook size I used is 5mm instead of 5.5 -would that make such a massive difference?

Ah.... the pattern says worsted weight yarn. I presume that and the hook is the problem.
Can anyone explain the yarn types please?

What yarn weight did you use? I'm guessing it will say DK or double knitting on the label. This is usually worked with a 4mm hook, so three sizes smaller than the pattern recommends - that's probably your sizing issue right there.

Yarn weights are called different things in different parts of the world. This chart might help you - www.ravelry.com/help/yarn/weights

Worsted is an American term, and a hook size of 5.5mm indicates quite a thick worsted too. You need to look for an Aran on this side of the pond, and I'd probably look carefully at the recommended hook sizes. I wouldn't buy anything for this pattern with a recommended hook size of less than 5mm.

Thanks that's really helpful.
Well it's finished and I fortunately have a friend with a 6 month old.....
And I got to practice my dc htc and tc!

I learnt this lesson on gauge too... used a bigger hook and yarn weight and instead of a toddler hat I ended up with one too big for me! If you're not using the same hook and yarn weight you need to do a gauge check (lots of patterns tell you the required gauge) to make sure you get it right!

To be honest, I never go by gauge or anything for hats. But hat sizing charts. So you increase the circle to the required diameter, and then you work down for the required depth for size xxx

Yes worsted is roughly equivalent to Aran. I have found that US patterns for knitting and crochet are often really confusing with their terms. Are you sure it was 5mm and not a size 5 US, which is equivalent to 3.75mm? (Although that wouldn't make sense with worsted yarn either).

I always find this site helpful. www.laughinghens.com/knitting-needle-sizes, sure there's something similar for crochet hooks.

That's massively helpful! Thanks everyone!
Happy NY
Think I'm going to do a blanket next....... size less crucial!