3.75 mm knitting needle
3.75 mm
US 5 · UK 9 · Sport to DK
What this size is for
A common substitute when a DK pattern comes out loose on 4 mm.
In each scale
| Diameter | 3.75 mm |
| US size | 5 |
| UK / Canadian size | 9 |
| Yarn weight | Sport to DK |
A US 5 and a UK 5 are not the same needle. This one is 3.75 mm; the British 5 is 5.5 mm. Buy by millimetre wherever the pattern allows it.
Nearby sizes
| mm | US | UK | Yarn |
|---|---|---|---|
| 2.75 | 2 | 12 | Fingering, 4-ply |
| 3 | 2/3 | 11 | Fingering |
| 3.25 | 3 | 10 | Fingering to sport |
| 3.5 | 4 | — | Sport |
| 3.75 | 5 | 9 | Sport to DK |
| 4 | 6 | 8 | DK |
| 4.5 | 7 | 7 | DK to worsted |
Frequently asked questions
What is a 3.75 mm knitting needle in US and UK sizes?
US 5 and UK 9. The millimetre figure is the actual diameter and the only one that means the same thing everywhere.
Is a US 5 the same as a UK 5?
No. A US 5 is 3.75 mm; a UK 5 is 5.5 mm. The scales run in opposite directions — American numbers grow with the needle and British ones shrink — so the same number is two different needles.
What yarn suits a 3.75 mm needle?
Sport to DK. A common substitute when a DK pattern comes out loose on 4 mm.
Why do the two scales run in opposite directions?
The British scale counts down from the thickest wire in a gauge, in the same way a wire gauge does — more drawing operations, higher number, thinner. The American scale simply counts up from the finest needle. Neither is wrong; they were never designed to be compared, and the only size where the numbers coincide is 4.5 mm, which is size 7 in both.