Something to be aware of when you start crocheting is there is a difference between UK & US terminology in addition to their different sizing convention for hooks, knitting needles and yarn weights (Australia also has a different version)
Crochet terms
| UK | USA |
| Double crochet | Single crochet |
| Half treble crochet | Half double crochet |
| Treble crochet | Double crochet |
| Double treble crochet | Treble crochet |
| Triple treble crochet | Double treble crochet |
| Tension | Gauge |
| Miss | Skip |
Hook & Needle Sizes
The majority of modern patterns give hook and needle sizes in mm.
However American patterns can use either a letter or a number and “vintage” UK & Canadian patterns could have used a number.
|
Metric (mm) |
USA | UK / Canada |
| 2 | 0 | 14 |
| 2.25 | B / 1 | 13 |
| 2.75 | C / 2 | 12 |
| 3 | 11 | |
| 3.25 | D / 3 | 10 |
| 3.5 | E / 4 | |
| 3.75 | F / 5 | 9 |
| 4 | G /6 | 8 |
| 4.5 | 7 | 7 |
| 5 | H / 8 | 6 |
| 5.5 | I / 9 | 5 |
| 6 | J / 10 | 4 |
| 6.5 | K / 10 ½ | 3 |
| 7 | 2 | |
| 7.5 | 1 | |
| 8 | L / 11 | 0 |
| 9 | M / 13 | 00 |
| 10 | N / 15 | 000 |
| 12 | 17 | |
| 15 | ||
| 16 | 19 | |
| 19 | 35 | |
| 20 | 36 | |
| 25 | 50 |
Yarn Weights
| UK | US | Australian | Hook size (mm) |
| 1 ply | Lace | 2 ply | 1.5 – 2.25 |
| 2 ply | Fingering | 3 ply | 2.25 – 3.5 |
| 4 ply | Sport | 5 ply | 3.5 – 4.5 |
| DK | DK | 8 ply | 4.5 – 5.5 |
| Aran | Worsted | 10 ply | 5.5 – 6.5 |
| Chunky | Bulky | 12 ply | 6.5 – 9 |
| Super chunky | Super bulky | 14 ply | 9+ |
