Free tool
Gauge Calculator
Turn your swatch into stitches and rows per inch, work out how many stitches a finished size needs, and check your gauge against a pattern so your project comes out right. Works for crochet and knitting, in inches or centimetres.
Your swatch
Crochet a swatch at least 6 in square, then count the stitches and rows across a flat section in the middle.
Your gauge
4.00
stitches per in
5.00
rows per in
16.0
stitches per 4 in
20.0
rows per 4 in
Stitches and rows for a size
Enter the finished size you want. We use your gauge to tell you how many stitches to start and how many rows to work.
Start with 160 stitches
Work about 250 rows
Check against a pattern
Enter the pattern's gauge (the stitches per 4 in it lists) to see if your fabric matches, and whether to change hook size.
Your gauge matches the pattern. Cast on as written.
Your numbers save to your browser automatically. Gauge changes with yarn, hook, and your tension, so swatch for every new project.
How to use it
- Crochet or knit a swatch at least 6 inches (15 cm) square in the stitch your pattern uses, then lay it flat without stretching.
- Count the stitches across a 4 inch (10 cm) section in the middle, and the rows up a 4 inch section. Enter both into Your swatch.
- Read your gauge, then use Stitches and rows for a size to size any project, or Check against a pattern to see if you need a different hook.
Why gauge matters
Gauge is the single most common reason a finished piece comes out the wrong size. Two crocheters using the same yarn and hook can get different gauges purely from tension. A difference of half a stitch per inch sounds tiny, but across a 40 inch sweater that is 20 stitches, which is several inches of fit. For anything worn, swatch first.
If you are new to all of this, the introduction to crochet covers reading a pattern, and the yarn weight converter helps you pick a yarn and hook to swatch with.
Frequently asked questions
What is gauge in crochet and knitting?
Gauge is how many stitches and rows fit in a given measurement, usually 4 inches or 10 cm. It depends on your yarn, hook or needle size, and personal tension. Matching gauge is what makes a finished piece come out the size the pattern intends.
How do I measure my gauge?
Make a swatch at least 6 inches (15 cm) square in the pattern stitch, then lay it flat without stretching. Count the stitches across a 4 inch (10 cm) section in the middle, and the rows up a 4 inch section. Enter those numbers above to get your gauge.
Why does my project come out the wrong size?
Almost always a gauge mismatch. If your fabric is tighter than the pattern, your piece comes out smaller, so go up a hook or needle size. If it is looser, go down a size. Swatch again after changing, since even half a stitch per inch adds up across a garment.
Do I really need to swatch?
For anything that has to fit, like a garment or a hat, yes. For a scarf or a blanket where exact size does not matter, you can skip it. A swatch costs about forty minutes and saves you from frogging a whole project that turned out the wrong size.
How many stitches do I cast on for a certain width?
Multiply your stitches per inch by the width you want, then round up. This calculator does it for you: enter your swatch and a finished width, and it returns the number of stitches to start with and the rows to work.
Keep your gauge with your project
CrochetZen saves your gauge alongside each project, tracks your rows, and spots dropped stitches with the AI camera. Free 3-day trial on iOS.