Millimeters to Japanese sizes
Type a value in mm to get it in JP instantly.
13JP
That's 1.2× as thick as the needle for worsted yarn, while the needle for chunky yarn is 1.08× thicker.
Convert the other way: JP to mm
What it means
Which yarn suits that needle?
Typical needle sizes for each yarn weight; the ball band and your tension swatch have the final word.
The math
How to convert mm to JP
US and UK sizes are tables: US 6 = UK 8 = 4 mm, US 8 = UK 6 = 5 mm. Japanese size n is 2.1 + 0.3 × n mm.
Example: 6 mm = 13 JP.
Every unit
That needle in every system
Tables
mm to JP conversion table
| mm | JP |
|---|---|
| 2.25 mm | 0.5 JP |
| 2.75 mm | 2.16667 JP |
| 3.25 mm | 3.83333 JP |
| 3.5 mm | 4.66667 JP |
| 3.75 mm | 5.5 JP |
| 4 mm | 6.33333 JP |
| 4.5 mm | 8 JP |
| 5 mm | 9.66667 JP |
| 5.5 mm | 11.3333 JP |
| 6 mm | 13 JP |
| 6.5 mm | 14.6667 JP |
JP to mm conversion table
| JP | mm |
|---|---|
| 0.5 JP | 2.25 mm |
| 2.17 JP | 2.751 mm |
| 3.83 JP | 3.249 mm |
| 4.67 JP | 3.501 mm |
| 5.5 JP | 3.75 mm |
| 6.33 JP | 3.999 mm |
| 8 JP | 4.5 mm |
| 9.67 JP | 5.001 mm |
| 11.3 JP | 5.49 mm |
| 13 JP | 6 mm |
| 14.7 JP | 6.51 mm |
Quick answers
Quick answers
- How many JP is 6 mm?
- 6 mm is 13 JP.
The units
About these units
Millimeters (mm)
The metric size: the needle’s diameter.
Japanese sizes (JP)
2.1 mm plus 0.3 mm per size.
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