<p>For hook sizes, it's always best to refer to the size of the hook in mm, if possible. This should be standard across all countries. Metric sizes are used in many countries including Australia and New Zealand. UK sizes are generally used in the UK and Canada. US sizes are generally used only in the US.</p>
<p>The equivalents (when applicable) are below. Note that some sites give different size conversions for the same hook and not all mm sizes are available in every system, which is why some sizes are listed under more than one mm size.</p>
<p>Crochet Hook Conversions:</p>
<div class="s-table-container">
<table class="s-table">
<thead>
<tr>
<th>Metric</th>
<th>US</th>
<th>UK</th>
</tr>
</thead>
<tbody>
<tr>
<td>2.00 mm</td>
<td>0</td>
<td>14</td>
</tr>
<tr>
<td>2.25 mm</td>
<td>1/B</td>
<td>13</td>
</tr>
<tr>
<td>2.50 mm</td>
<td>2</td>
<td>12</td>
</tr>
<tr>
<td>2.75 mm</td>
<td>2/C</td>
<td>11/12</td>
</tr>
<tr>
<td>3.00 mm</td>
<td>3</td>
<td>11</td>
</tr>
<tr>
<td>3.25 mm</td>
<td>3/D</td>
<td>10</td>
</tr>
<tr>
<td>3.50 mm</td>
<td>4/E</td>
<td>9</td>
</tr>
<tr>
<td>3.75 mm</td>
<td>5/F</td>
<td>9</td>
</tr>
<tr>
<td>4.00 mm</td>
<td>6/G</td>
<td>8</td>
</tr>
<tr>
<td>4.50 mm</td>
<td>7</td>
<td>7</td>
</tr>
<tr>
<td>5.00 mm</td>
<td>8/H</td>
<td>6</td>
</tr>
<tr>
<td>5.50 mm</td>
<td>9/I</td>
<td>5</td>
</tr>
<tr>
<td>6.00 mm</td>
<td>10/J</td>
<td>4</td>
</tr>
<tr>
<td>6.50 mm</td>
<td>10½/K</td>
<td>3</td>
</tr>
<tr>
<td>7.00 mm</td>
<td>n/a</td>
<td>2</td>
</tr>
<tr>
<td>7.50 mm</td>
<td>n/a</td>
<td>1</td>
</tr>
<tr>
<td>8.00 mm</td>
<td>11/L</td>
<td>0</td>
</tr>
<tr>
<td>9.00 mm</td>
<td>13/M/N</td>
<td>00</td>
</tr>
<tr>
<td>10.0 mm</td>
<td>15/N/P</td>
<td>000</td>
</tr>
<tr>
<td>15.0 mm</td>
<td>P/Q</td>
<td>n/a</td>
</tr>
<tr>
<td>16.0 mm</td>
<td>Q</td>
<td>n/a</td>
</tr>
<tr>
<td>19.0 mm</td>
<td>S</td>
<td>n/a</td>
</tr>
</tbody>
</table>
</div>
CC BY-SA 3.0
2016-04-27T17:26:34.993Z
If there are other systems of hook measurement not included here that would be useful, please let me know and I will add them! I want this to be a useful FAQ for crochet hook size conversion.
Catija
CC BY-SA 3.0
2016-04-27T18:08:54.677Z
I am very happy that you have the text as supposed to a picture. This should help get more view for sure.
Matt
CC BY-SA 3.0
2016-04-27T19:13:40.340Z
Please expand your table to include hooks smaller than 2mm. In my country they are described in milimeters, but I think their names were weird for UK and/or US
jkadlubowska
CC BY-SA 3.0
2016-04-27T19:15:19.767Z
@jkadlubowska You mean like the tiny hooks used for lace tatting and crocheted jewelry making?
Catija
CC BY-SA 3.0
2016-04-27T20:42:44.997Z
I've been doing some research @jkadlubowska and I'm afraid they're a bit out of my depth... There seems to be a lot of disagreement regarding the sizes of these hooks. There are at least two different charts of equivalents between the US sizes and their mm equivalents and two charts for UK to mm, so I'll have to do some more work before I can fully address that part of the sizing chart.
Catija
CC BY-SA 3.0
2016-04-30T20:22:53.803Z
Also glad about a text-based table!
Over time, the designations have changed. A US steel crochet hook I bought twenty years ago has a different designation from what the same manufacturer now sells, and twenty years isn't much.
skg
CC BY-SA 3.0
2016-04-30T20:25:46.257Z
I have 1.75, 1.5, and 0.75 mm steel hooks for crochet. They're made by Japanese and German companies and still sold. The 0.75 works well with size 80 cordonnet thread or six-strand cotton embroidery floss. I don't think they have letter-based designations in the US, however (which is where I live).
skg
CC BY-SA 4.0
2016-04-27T17:25:19.017Z
2022-10-14T20:22:14.547Z
2022-10-14T20:22:14.547Z
Catija
<p>There are smaller crochet hooks as well, and they have a different numbering system. These are often called Steel Crochet Hooks, and are the type of hooks you'd use with crochet thread.</p>
<div class="s-table-container">
<table class="s-table">
<thead>
<tr>
<th>Metric</th>
<th>US</th>
<th>UK</th>
</tr>
</thead>
<tbody>
<tr>
<td>3.50 mm</td>
<td>00</td>
<td></td>
</tr>
<tr>
<td>3.25 mm</td>
<td>0</td>
<td>0</td>
</tr>
<tr>
<td>2.75 mm</td>
<td>1</td>
<td>1</td>
</tr>
<tr>
<td>2.25 mm</td>
<td>2</td>
<td>1 1/2</td>
</tr>
<tr>
<td>2.10 mm</td>
<td>3</td>
<td>2</td>
</tr>
<tr>
<td>2.00 mm</td>
<td>4</td>
<td>2 1/2</td>
</tr>
<tr>
<td>1.90 mm</td>
<td>5</td>
<td>3</td>
</tr>
<tr>
<td>1.80 mm</td>
<td>6</td>
<td>3 1/2</td>
</tr>
<tr>
<td>1.65 mm</td>
<td>7</td>
<td>4</td>
</tr>
<tr>
<td>1.50 mm</td>
<td>8</td>
<td>4 1/2</td>
</tr>
<tr>
<td>1.40 mm</td>
<td>9</td>
<td>5</td>
</tr>
<tr>
<td>1.30 mm</td>
<td>10</td>
<td>5 1/2</td>
</tr>
<tr>
<td>1.10 mm</td>
<td>11</td>
<td>6</td>
</tr>
<tr>
<td>1.00 mm</td>
<td>12</td>
<td>6 1/2</td>
</tr>
<tr>
<td>0.85 mm</td>
<td>13</td>
<td>7</td>
</tr>
<tr>
<td>0.75 mm</td>
<td>14</td>
<td></td>
</tr>
</tbody>
</table>
</div>
<p>Source: <a href="https://sarahmaker.com/crochet-hook-sizes/" rel="nofollow noreferrer">Crochet Hook Size Chart</a></p>

CC BY-SA 4.0
2022-10-14T19:30:04.323Z
2022-10-14T19:30:04.323Z
sarahst
<p>Please note that in Canada metric sizing is the predominant measurement used for crochet hooks; i.e. 1.00mm, 1.30mm, 3.00mm, 4.25mm, 5.00mm, 6.50mm etc.  Very rarely these days is the U.K. system used in Canada.<br>
Certainly, it would be less confusing and more helpful if the metric system  were for crochet hooks around the world.  It is already used in many areas.
Hooks smaller than 2.00mm are made by a variety of manufacturers in full steel and steel with ergonomically made handles by a variety of manufacturers. </p>

CC BY-SA 4.0
2020-01-23T05:32:35.020Z
2020-01-23T05:32:35.020Z
Pamela
<p>The UK and US use numbered or lettered hook sizes in their patterns rather than a standardized measurement. What are the conversions between the hook sizes depending on whether I'm using US or UK patterns?</p>

<crocheting><crochet-hooks>
What is the conversion for UK and US crochet hooks to mm?
Catija
# What is the conversion for UK and US crochet hooks to mm?

(Asked by: username_0 on 2016-04-27)

The UK and US use numbered or lettered hook sizes in their patterns rather than a standardized measurement. What are the conversions between the hook sizes depending on whether I'm using US or UK patterns?

**Tags:** crocheting, crochet-hooks


---

## 3 answers

### Answer by username_0 on 2016-04-27. Score: 15

For hook sizes, it's always best to refer to the size of the hook in mm, if possible. This should be standard across all countries. Metric sizes are used in many countries including Australia and New Zealand. UK sizes are generally used in the UK and Canada. US sizes are generally used only in the US.

The equivalents (when applicable) are below. Note that some sites give different size conversions for the same hook and not all mm sizes are available in every system, which is why some sizes are listed under more than one mm size.

Crochet Hook Conversions:

| Metric | US | UK |
| --- | --- | --- |
| 2.00 mm | 0 | 14 |
| 2.25 mm | 1/B | 13 |
| 2.50 mm | 2 | 12 |
| 2.75 mm | 2/C | 11/12 |
| 3.00 mm | 3 | 11 |
| 3.25 mm | 3/D | 10 |
| 3.50 mm | 4/E | 9 |
| 3.75 mm | 5/F | 9 |
| 4.00 mm | 6/G | 8 |
| 4.50 mm | 7 | 7 |
| 5.00 mm | 8/H | 6 |
| 5.50 mm | 9/I | 5 |
| 6.00 mm | 10/J | 4 |
| 6.50 mm | 10½/K | 3 |
| 7.00 mm | n/a | 2 |
| 7.50 mm | n/a | 1 |
| 8.00 mm | 11/L | 0 |
| 9.00 mm | 13/M/N | 00 |
| 10.0 mm | 15/N/P | 000 |
| 15.0 mm | P/Q | n/a |
| 16.0 mm | Q | n/a |
| 19.0 mm | S | n/a |

> **Comments:**
> **username_0**: If there are other systems of hook measurement not included here that would be useful, please let me know and I will add them! I want this to be a useful FAQ for crochet hook size conversion.  
> **username_1**: I am very happy that you have the text as supposed to a picture. This should help get more view for sure.  
> **username_2**: Please expand your table to include hooks smaller than 2mm. In my country they are described in milimeters, but I think their names were weird for UK and/or US  
> **username_0**: @username_2 You mean like the tiny hooks used for lace tatting and crocheted jewelry making?  
> **username_0**: I've been doing some research @username_2 and I'm afraid they're a bit out of my depth... There seems to be a lot of disagreement regarding the sizes of these hooks. There are at least two different charts of equivalents between the US sizes and their mm equivalents and two charts for UK to mm, so I'll have to do some more work before I can fully address that part of the sizing chart.  
> **username_3**: Also glad about a text-based table! Over time, the designations have changed. A US steel crochet hook I bought twenty years ago has a different designation from what the same manufacturer now sells, and twenty years isn't much.  
> **username_3**: I have 1.75, 1.5, and 0.75 mm steel hooks for crochet. They're made by Japanese and German companies and still sold. The 0.75 works well with size 80 cordonnet thread or six-strand cotton embroidery floss. I don't think they have letter-based designations in the US, however (which is where I live).  

---

### Answer by username_4 on 2022-10-14. Score: 2

There are smaller crochet hooks as well, and they have a different numbering system. These are often called Steel Crochet Hooks, and are the type of hooks you'd use with crochet thread.

| Metric | US | UK |
| --- | --- | --- |
| 3.50 mm | 00 |  |
| 3.25 mm | 0 | 0 |
| 2.75 mm | 1 | 1 |
| 2.25 mm | 2 | 1 1/2 |
| 2.10 mm | 3 | 2 |
| 2.00 mm | 4 | 2 1/2 |
| 1.90 mm | 5 | 3 |
| 1.80 mm | 6 | 3 1/2 |
| 1.65 mm | 7 | 4 |
| 1.50 mm | 8 | 4 1/2 |
| 1.40 mm | 9 | 5 |
| 1.30 mm | 10 | 5 1/2 |
| 1.10 mm | 11 | 6 |
| 1.00 mm | 12 | 6 1/2 |
| 0.85 mm | 13 | 7 |
| 0.75 mm | 14 |  |

Source: [Crochet Hook Size Chart](https://sarahmaker.com/crochet-hook-sizes/)


---

### Answer by username_5 on 2020-01-23. Score: 1

Please note that in Canada metric sizing is the predominant measurement used for crochet hooks; i.e. 1.00mm, 1.30mm, 3.00mm, 4.25mm, 5.00mm, 6.50mm etc. Very rarely these days is the U.K. system used in Canada.  
Certainly, it would be less confusing and more helpful if the metric system were for crochet hooks around the world. It is already used in many areas.
Hooks smaller than 2.00mm are made by a variety of manufacturers in full steel and steel with ergonomically made handles by a variety of manufacturers.


---

