Steel crochet hook sizes: chart and mm conversion

Steel crochet hook sizes: US numbers and millimeters

Steel hooks are numbered the other way round from regular hooks: the higher the number, the smaller the hook.
Makers do not all number steel hooks alike, so the same number can be a different size on another maker's hook. The millimeters marked on the hook are the measurement: go by them.
Every row here is given the same way by two charts. Where one chart alone lists a number at another size, that size is left out.

Steel hooks are the small hooks used for crochet thread and lace-weight yarn.
The higher the number, the smaller the hook. Regular hooks run the other way.
Go by the millimeters marked on the hook or its package. The number is a name for the size, and makers do not all use the numbers the same way.
Whatever the number says, the right hook is the one that gives your pattern's gauge. Make a swatch and compare it with the gauge the pattern states.

What size is a steel hook 7 in millimeters?: 1.65 mm.
What size is a number 10 steel crochet hook?: 1.3 mm.
Which is smaller, a steel hook 4 or a steel hook 12?: The 12. It is 1 mm, and the 4 is 2 mm: steel hook numbers rise as the hooks get smaller.
What steel hook is 1.5 mm?: A steel hook 8 in the charts. Check the millimeters on your own hook, because makers number steel hooks differently.

Is a higher number a bigger steel hook?: No. Steel hook numbers run the other way from regular hooks: on this chart the 14 is the smallest hook, at 0.75 mm, and the 00 is the largest, at 3.5 mm.
What are steel crochet hooks used for?: Crochet thread and lace-weight yarn. They are the smallest hooks there are.
The number on my hook is not the size this chart gives. Which is right?: The millimeters on your hook. Makers do not number steel hooks alike, so go by the millimeters and check your gauge with a swatch.

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Hook size chart What size is my hook, in millimeters and as a US letter or number?
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