The Right Hook for Yarn Weight

the right hook for yarn weight

Table of Contents

Have you ever wondered what your yarn means when they talk about weight, or why the heck it matters what hook you need to use on your projects? Let’s dive in and find the right hook for yarn weight.

Still learning about all of the symbols and numbers on a yarn label?

What does “yarn weight” even mean?

As you see on the chart below, the different numbers for yarn weight, from 0 to 7. This runs from Lace (0) to Jumbo (7). When you purchase your yarn, you’ll see one of these numbers on the label. The term “weight” doesn’t necessarily refer to how heavy a yarn it; moreso, it refers to the thickness.

Lace yarn (0) is typically used when you want the appearance of lace, such as for shawls, doilies, or lightweight undergarments and accessories. You can even crochet earrings!!

Super Fine yarn (1) is typically used for baby items, socks, or shawls. Actually, a lot of your typical “lacy” items fall into this category rather than the lace yarn category.

Fine yarn (sport yarn) (2) is used for wraps, socks, and other delicate accessories. This is also a great weight to use for lighter afghans.

Light yarn (3)is used for garments and heavier baby items, such as sweaters and heaver afghans.

Medium yarn (4)is the most common weight of yarn. It’s great for beginners because it’s easy to work with, not too thin and not too thick. This is also a great weight for typical afghans.

Bulky (5)is great for sweaters, scarves, throw blankets, and rugs.

Super Bulky (6)is used for scarves and hats as it is a thicker yarn.

Jumbo (7)is the thickest yarn weight and is typically used for arm knitting, which has become a popular trend in recent years amongst younger generations! Therefore, it is great for quickly working up blankets.

Why the heck do different countries have different measurements and names?

I mean… same reason most everyone else uses the metric system and the U.S. doesn’t, but hey… what do I know? Need a good conversion chart? Check out this one from Crochet Hooks YouCrochet Hooks You.

The Right Hook for Yarn Weight

This is all shown in the chart at the bottom of this post, but let’s spell it out here just because I feel like it.

For Lace (0), use a 1.4 – 2.25mm steel or regular; 2-14 steel or B-1 regular (US sizes); 1 1/2 – 7 steel or 13-14 regular (UK sizes).

For Super Fine (1), use 2.25 – 3.5mm steel or regular; B-1, C-2, D-3, or E-4 steel or regular (US sizes); 1 1/2 steel or 10-13 regular (UK sizes).

For Fine (2), use 3.5 – 4.5mm steel or regular; E-4, F-5, G-6 or 7 steel or regular (US sizes); 7-9 steel or regular (UK sizes).

For Light (3), use 4.5 – 5.5mm steel or regular; 7, H-8, or I-9 steel or regular (US sizes); 5-7 steel or regular (UK sizes).

For Medium (4), use 5.5 – 6.5mm steel or regular hook; I-0, J-10, K-10.5 steel or regular(US sizes); 3-5 steel or regular (UK sizes).

For Bulky (5), 6.5 – 9mm steel or regular; K-10.5, L-11, M/N-13 steel or regular (US sizes); 00-3 steel or regular (UK sizes).

For Super Bulky (6), use 9 – 15mm steel or regular; M/N-13, N/P-15, O, or P/Q steel or regular (US sizes); 00 or 000 steel or regular (UK sizes).

For Jumbo (7), use 15mm or larger steel or regular; P/Q, S, U, or Y (US sizes). From my knowledge as of this date, Jumbo has not yet been sized in UK, at least as far as I can find in my research.

The Right Hook for Yarn Weight – Can I use a different hook?

Abso-freaking-lutely. Changing the size hook you use with a certain yarn can either make your project tighter or looser depending on which way you go on the scale. Yarn labels typically have a recommended hook size to use with that weight of yarn, which is what you’ll see in the chart below. The pattern you’re using may also have a suggested yarn weight and hook size to get the gauge on which they based their pattern/project.

So, here are a couple reasons you may want to change your hook size:

You tend to hold a looser or tighter tension and need to adjust from the pattern. If you know ahead of time that you crochet more loosely than average, you may want to decrease your hook size to ensure that you stay within the gauge of the pattern. If you tend to crochet tighter than average, going up a hook size may be your best best.

You want the project to end up smaller or larger than the pattern. For whatever reason, maybe you want to decrease or increase the size of the project. A smaller hook will help to decrease the gauge of your project, while a larger hook will help to increase the gauge.

Need help reading your basic crochet terms? 35+ Basic Crochet Terms & Abbreviations

On the chart below, you will find the recommended size hooks to use for yarn weight. At the top is the yarn weight, then a description of the yarn. (See above for what the weights are best used for.) Below that you will find hook size in millimeters, then US sizes, followed by UK sizes. 

crochet hooks and yarn weight
the right hook for yarn weight

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