Crochet gauge calculator

Gauge (called tension in the UK) is how many stitches and rows fit in a set width and height of your fabric, and every size in a pattern depends on it. This calculator turns a swatch you have measured into stitches and rows per inch or centimetre, the standard 4 in and 10 cm figures, and the number of stitches and rows for the size you want to make. It accepts half stitches and any measuring width, so you do not have to round anything before you start.

How to use the gauge calculator

1. Crochet a swatch at least 6 in (15 cm) square in the yarn, hook and stitch pattern you will use, then wash or block it the way you will treat the finished piece.
2. Choose inches or centimetres, and US or UK terms. Switching units converts the numbers already in the form.
3. Count the stitches across the middle of the swatch, away from the edges, and enter them with the width they cover. Half stitches count: 14.5 is fine.
4. Count the rows and enter them with the height they cover. If you only need stitch gauge, leave the row fields blank.
5. Optionally, enter the width and length you want, to get stitch and row counts for your project.

How the calculator works

Stitch gauge is the stitches you counted divided by the width they cover; row gauge is the rows divided by the height.

Stitch gauge = stitches counted ÷ width measured

Row gauge = rows counted ÷ height measured

The calculator shows both per single inch or centimetre, per 4 in and per 10 cm. It converts with 1 in = 2.54 cm exactly, so 4 in (10.16 cm) and 10 cm are kept apart rather than treated as the same. The difference is 1.6%: 15 stitches over 4 in is 3.75 stitches per inch, which is 14.76 stitches per 10 cm, not 15. On a 200-stitch sweater body that gap is more than 3 stitches.

For your project, it multiplies the width you want by the stitch gauge and the length by the row gauge:

Stitches = width × stitch gauge

Rows = length × row gauge

You cannot work part of a stitch, so the table shows each count rounded down, to the nearest whole number and rounded up. When both gauges are filled in, it also shows how tall one stitch is compared with its width (stitch gauge ÷ row gauge). Single crochet stitches are close to square; double crochet stitches are usually much taller than they are wide. The circle, border and chart calculators rely on that shape.

Reading your results

• Stitches and rows per 4 in or 10 cm: compare these with the gauge box in your pattern or on the yarn label. If they do not match, the gauge difference calculator shows how big your piece will come out.
• Counts for your project: the closest whole number suits most blankets, scarves and flat pieces. Round down when a little narrower is safer, such as a fitted garment; round up when a little extra is useful, such as a panel that loses width in a seam.
• The count is stitches in a row, not the starting chain. Add the turning chain for your stitch, and fit any stitch repeat, with the foundation chain calculator.

Worked example

You want a baby blanket 32 in wide and 36 in long in half double crochet (UK half treble). Your blocked swatch has 13.5 stitches and 10 rows over a 4 in square.

• Stitch gauge: 13.5 ÷ 4 = 3.375 stitches per inch, or 13.29 per 10 cm.
• Row gauge: 10 ÷ 4 = 2.5 rows per inch, or 9.84 per 10 cm.
• Stitches across: 32 × 3.375 = 108.
• Rows: 36 × 2.5 = 90.
• Stitch height ÷ width: 3.375 ÷ 2.5 = 1.35.

US and UK terms

Switch the calculator to UK terms and every stitch name in the results changes; the numbers stay the same. UK names are one step taller than US names for the same stitch:

• US single crochet (sc) = UK double crochet (dc)
• US half double crochet (hdc) = UK half treble (htr)
• US double crochet (dc) = UK treble (tr)
• US treble (tr) = UK double treble (dtr)

Accuracy and limits

• The arithmetic is exact, and our automated tests check it against worked examples like the one above. The answer is only as good as your swatch.
• Small swatches magnify counting errors. Measure over 4 in (10 cm) or more where you can; the calculator notes when your measured width is shorter.
• The counts are for plain rows. They do not add a turning chain or round to a stitch repeat.
• If you will add a border, take its width off both sides first, or use the stitch and row calculator, which subtracts it for you.
• Heavy blankets and lace stretch under their own weight more than a small swatch shows.

Common mistakes

1. Measuring edge to edge. The foundation chain, last row and turning chains sit at a different tension from the middle. Measure the centre of a larger swatch.
2. Rounding half stitches away. Counting 14.5 stitches as 14 over 4 in is a 3.4% error, which on a 44 in sweater is about 1.5 in.
3. Measuring before blocking. Wool, cotton and other natural fibres often relax when washed. Measure the swatch in the state the finished piece will be worn or used; the blocking calculator helps when you need both.
4. Stretching the swatch. Lay it flat without pulling, and use a rigid ruler rather than a soft tape.

Tips for more accurate results

• Mark exactly 4 in (10 cm) with two pins, then count the stitches between them.
• On textured or lace stitches, count two different rows and enter the average.
• If your stitch gauge matches but your rows are too tall or short, the swatch troubleshooter suggests what to change before you swap hooks.

Frequently asked questions

Related guides and tools

• How to measure a gauge swatch