Crochet Yarn Calculator
Crochet yarn calculator works out Stitches to chain or cast on and Rows to work from Project, Standard size and Finished width. The default figures on this page give yarn needed of 366.7 yards; change any entry and the result, the working and the sources update together.
Your figures
Updates as you typeHow this is worked out
5 steps
- Gauge: 14 stitches and 8 rows over 4 in, so 3.5 stitches and 2 rows per in.
- Chain 140 for a 40 in width, and work 100 rows for 50 in.
- Estimated from stitch count and yarn weight: about 333 yards before allowance.
- Adding 10% gives 367 yards.
- At 200 yards a skein, buy 2 skeins.
Its 5 worked examples are re-run on every release, last on 15 September 2026. What changed
Sources and references
3 sources
What the crochet yarn calculator calculates
Turns a gauge swatch into stitch and row counts for any finished size, and estimates the yarn needed in yards, metres, grams and skeins.
How to use this crochet yarn calculator
Enter Project, Standard size, Finished width and Finished length. Stitches to chain or cast on updates as you type, and “Use a worked example” loads checked figures you can adjust. Change one figure at a time to see what drives the result.
How the result is worked out
Open “How this is worked out” beside the result for the step-by-step calculation behind Stitches to chain or cast on, Rows to work and Total stitches in the project.
The method follows Craft Yarn Council, Standard Yarn Weight System, Craft Yarn Council, standard blanket and garment sizing charts and Yarn requirement scales with finished area against a measured swatch: yards = swatchYards x (projectArea / swatchArea)..
Gauge of 14 stitches per 4 inches over a 40 inch width example
With Project: blanket, Finished width: 40, Finished length: 50, Stitches in the gauge swatch: 14, the calculator returns Stitches to chain or cast on: 140, Rows to work: 100. This example is checked against an independent source in the test suite.
What you can compare
Change one input at a time to see how it affects Stitches to chain or cast on, Rows to work and Total stitches in the project. The inputs you can vary are Project, Standard size, Finished width, Finished length, Finished diameter and Measurement unit.
Results are general information, not financial, tax, legal, medical or engineering advice. Check any decision that matters with a qualified professional.
See something wrong? Report a problem with this calculator
Frequently asked questions
How to calculate how much yarn you need for crochet?
Turns a gauge swatch into stitch and row counts for any finished size, and estimates the yarn needed in yards, metres, grams and skeins. Open “How this is worked out” beside the result to see each step for your own figures.
Is there a yarn calculator app available?
Turns a gauge swatch into stitch and row counts for any finished size, and estimates the yarn needed in yards, metres, grams and skeins. On the figures this page opens with — finished width 40, finished length 50 and stitches in the gauge swatch 14 — the yarn needed is 366.7 yards. Put your own figures in their place and the working updates beside the result.
How much yarn do I need to crochet a 50x60 blanket?
On the figures this page opens with — finished width 40, finished length 50, stitches in the gauge swatch 14 and rows in the gauge swatch 8 — the yarn needed is 366.7 yards. No single number fits everyone: change any figure above and the answer updates as you type, with each step of the arithmetic beside it.
How do I convert grams of yarn to yards for crochet?
It needs Project, Standard size, Finished width, Finished length, Finished diameter and Measurement unit. Nothing else is required, and the figures stay in your browser.
How do I calculate the amount of yarn I need?
The result gives Stitches to chain or cast on, Rows to work, Total stitches in the project, Yarn needed, Skeins to buy and Finished width, each labelled with its unit so the figure can be read on its own.
What information do I need for the crochet yarn calculator?
You need Project, Standard size, Finished width, Finished length, Finished diameter, Measurement unit, Stitches in the gauge swatch and Rows in the gauge swatch. The page opens with default figures that give yarn needed of 366.7 yards, so you can see the scale before entering your own.