Useful And Downloadable Conversion Chart For American/British Crochet Stitches & Hook Sizes

Gabriela

American and British crochet use the same words for different stitches. Not similar stitches — different ones. Follow a UK pattern as though it were American and your work will come out wrong from the very first row.

Here is everything you need to translate between them, plus the hook sizes, all on one page.

US to UK stitch conversion

This is the table that matters. Notice that every UK name is one step “bigger” than the American one.

United States Abbrev. United Kingdom Abbrev.
Chain ch Chain ch
Slip stitch sl st Slip stitch ss
Single crochet sc Double crochet dc
Half double crochet hdc Half treble crochet htr
Double crochet dc Treble crochet tr
Treble crochet tr Double treble dtr
Double treble dtr Triple treble trtr
Skip sk Miss miss
Gauge — Tension —
Yarn over yo Yarn over hook yoh
Worsted weight — Aran —

How to tell which one a pattern is using

Patterns rarely say. Use these three tests, in order:

  1. Look for “single crochet”. The UK has no such stitch. If you see it anywhere, the pattern is American. This settles it most of the time.
  2. Look at the smallest stitch used. If the most basic stitch in the whole pattern is “double crochet”, it is British. In an American pattern, dc is a mid-height stitch and sc would appear somewhere.
  3. Look for “tension” instead of “gauge”, or “miss” instead of “skip”. Both are British.

If a granny square pattern tells you to work clusters of three double crochet, that is American. If it says three treble, it is British — and the two produce the same square, because UK treble is US double.

Crochet hook size conversion

Millimetres are the only measurement that never lies. American letter sizes and old British numbers both vary slightly between manufacturers, so when a pattern gives both, trust the millimetres.

Crochet hook size chart converting metric millimetres to US letter sizes and old UK numbers, with the yarn weight each hook suits
Save this one for the yarn aisle. The disc on the left is drawn to scale, so you can see how much difference a millimetre actually makes.
Metric US UK (old) Typical yarn weight
2.25 mm B/1 13 1 – Super fine
2.75 mm C/2 12 1 – Super fine
3.25 mm D/3 10 2 – Fine
3.5 mm E/4 9 2 – Fine
3.75 mm F/5 9 3 – Light
4.0 mm G/6 8 3 – Light
4.5 mm 7 7 3 – Light
5.0 mm H/8 6 4 – Medium (most common)
5.5 mm I/9 5 4 – Medium
6.0 mm J/10 4 4 – Medium
6.5 mm K/10½ 3 5 – Bulky
8.0 mm L/11 0 5 – Bulky
9.0 mm M/13 00 6 – Super bulky
10.0 mm N/15 000 6 – Super bulky
11.5 mm P/16 — 6 – Super bulky
15.0 mm Q — 7 – Jumbo
19.0 mm S — 7 – Jumbo

Steel hooks for thread crochet

Thread crochet uses an entirely separate numbering system, and it runs backwards — the higher the number, the smaller the hook.

US steel Metric
00 2.70 mm
1 2.25 mm
4 2.00 mm
7 1.65 mm
10 1.30 mm
14 0.90 mm

Things that catch people out

  • The stitch heights still match. A UK treble and a US double crochet are the same physical stitch. You are translating names, not learning new techniques.
  • Australian and New Zealand patterns use UK terms. So do most South African and Irish ones.
  • Older American patterns can use UK terms. Anything printed before roughly 1960 is worth checking against the row count.
  • Hook letters and numbers disagree between brands. American hooks carry both a letter and a number, and manufacturers do not always pair them the same way. Go by millimetres.
  • “Aran” on a UK label means worsted. Same weight 4, different word.

Related guides

Where these standards come from

Hook equivalents follow the Craft Yarn Council hook and needle standards, and the thread hook sizes come from their steel hook and thread size chart. US and UK stitch names are long-established craft terminology that belongs to nobody, but the tables, explanations and worked examples on this page are our own.

Not sure which hook to buy? Read our guide to the best crochet hooks and how to choose them.

More patterns you’ll like

Related posts