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Crochet Hook Sizes – Handy Size Chart & All The Sizing Facts

There are many techniques to learn in crochet. Understanding crochet hook sizes is just part of the knowledge you need to acquire. Don’t worry. It’s simple and the charts below will help you.

For a comprehensive look at all things hooks, please visit my post – Crochet Hooks – My Complete Guide To All The Different Types & Styles.

Crocheting is such a wonderful craft, full of creative stitches, patterns and beautiful yarns. Knowing about hooks is part of the learning.

Table Of Contents

What Are All The Sizes Of Crochet Hooks?

Crochet Hook Conversion Chart

Metric/AUST/NZUSUK/Canada
2.00 mm14
2.25 mmB/113
2.50 mm12
2.75 mmC/211
3.125 mmD
3.25 mmD/310
3.5 mmE/4
3.75 mmF/59
4.00 mmG/68
4.25 mmG
4.50 mmUS77
5.00 mmH/86
5.50 mmI/95
6.00 mmJ/104
6.50 mmK/10.53
7.00 mm2
8.00 mmL/110
9.00 mmM/1300
10.00 mmN/15000
11.50 mmP/16
15.75/16 mmQ
19 mmS
(Based On Standards From The Craft Council)

Crochet Thread Hook Sizes / Steel Hook Crochet Sizes

MetricUS
3.50 mm00
3.25 mm0
2.75 mm1
2.70 mm00
2.55 mm0
2.35 mm1
2.25 mm2
2.20 mm2
2.10 mm3
2 mm4
1.90 mm5
1.80 mm6
1.75 mm4/0
1.70 mm5
1.65 mm7
1.60 mm6
1.50 mm8/7/2
1.40 mm9/8
1.30 mm10
1.25 mm9/4
1.15 mm10
1.10 mm11
1.05 mm11
1 mm12/6
0.95 mm13
0.90 mm14/8
0.85 mm13
0.75 mm14/10
0.60 mm12
(Based on the Craft Yarn Council’s standards.)

As you can see from the chart, the hook size varies from place to place. It’s important to know the conversions. Helpful when you want to crochet a pattern written in another country.

The diameter of a hook shaft determines the size of the hook and the size of the stitches. Hook sizes are measured in millimeters and are available from as small as 2 mm to 20 mm or bigger!

Hooks can be labeled with US sizes which uses numbers and letters. A US size G hook is 4.25mm in diameter. In the UK and Canada they also use numbers.

Australia and New Zealand use the metric sizes. The chart above is a great reference for comparison.

Usually the bigger or thicker the yarn the bigger hook you need. Chunky wool uses a bigger crochet hook.

Steel hooks are also known as “thread hooks” and should only be used for fine lace thread. They come in numbered sizes that get larger as the diameter or millimeters gets smaller.

These crochet hooks vary in size from the 0.6 mm thickness of size 12 to the 3.25 mm thickness of size 00. You can find conversion for thread hooks above.

How Do You Know What Size Crochet Hook To Use?

Choosing the right sized crochet hook follows a process.

In most crochet patterns, they have a suggested gauge with a certain crochet hook. This shows how many stitches you should have per inch.

You should do a swatch of about 4 inches in the stitch pattern you’re going to use in your project. Wash your swatch, let it dry and measure your stitches. Super important for crocheting items suchs a a sweater or top.

If your square is smaller than what the pattern calls for, size up a hook. Or down a size if your square is too large.

If you’ve bought yarn and don’t have a pattern in mind, the label has a suggestion for the hook size to use and also what gauge you should get. 

You’ll find a crochet hook size to suits you best for the projects you make.

Types Of Crochet Hooks

The types of crochet hooks vary not only in size but in materials they’re made from. I go into more detail in my Hooks Guide. Below is an overview.

Steel: These crochet hook sizes are the smallest. Refer to the chart above. Used for fine thread crocheting, such as doilies.

Aluminum: The most popular hook choice because the yarn glides smoothly.  Aluminum crochet hooks are available in a large range of sizes. 

Plastic: Available in a wide range of sizes. Great for beginners because they are cost effective. 

Bamboo: Available in many sizes but not the smallest sizes. The largest is a 25mm.

Wood: Wood is used to make crochet hooks as well. They often have beautifully carved handles or are just a regular shape.

Tunisian: Longer than a standard crochet hook. This means more stitches can be held on the hook as you work. 

Ergonomic: The specially designed shape of the handle is to reduce the strain in your working hand. 

The Knook: A long crochet hook with a hole through one end. You thread a piece of yarn through the hole. You can create stitches looking like knitting.

Your Questions Answered

What Is The Most Common Crochet Hook Size?

A G/H crochet hook is excellent for beginners. It’s also used for all sorts of projects. A 6 in Canada and the UK, and 5.00mm in metric.

How Does Hook Size Affect Crochet?

The smaller the hook size, the smaller the gaps between the yarn and tighter the connections between the loops. For a bigger crochet hook, the opposite is true. Keep in mind the yarn weight also affects the finished product.

What Happens If I Use A Bigger Crochet Hook?

The gauge will be larger, thus making a bigger finished item.

What Size Is A 2.5 mm Crochet Hook?

In US sizing, it’s still know as a 2.5mm crochet hook, as there is no direct equivalent. In UK/Canada sizing, it’s 12.

What Is A Size G Crochet Hook?

In US sizing, a size G crochet hook is also known as 6. In metric, it’s 4.00mm and in the UK & Canada, it’s 8.

What Is A Size 7 Crochet Hook?

A US size 7 and a size 7 in the UK & Canada are the same size, but in metric it’s 4.50mm.

What Is A Size 8 Crochet Hook?

Also known as size H in the States, it’s a 6 in Canada and the UK, and is 5.00mm in metric sizing.

What Size Crochet Hook For Blanket?

Generally the best size crochet for a blanket is H/8 (5mm). Though it depends on the yarn weight of the yarn you’re using.

What Size Crochet Hook For 4ply Wool?

The best size crochet hook for 4ply wool is 2.50mm – 3.00mm, US E/4 and 12-9 for UK/Canada.

Come back to this post whenever you need to use the Crochet Hook Sizes conversion chart. Happy Crocheting!

Something I forgot? Or have a question? Leave a comment at the end.

About Jodie Morgan

Hi. I’m Jodie Morgan, owner and creator of Crochet Penguin. (Yes, I’m a real person :) )

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