Why do I need a swatch?

Because the yarn a crochet stitch takes depends on the stitch, the hook, the yarn and your hands. Rules of thumb are off by a lot, so the calculator only works from something you crocheted yourself.

Which of the three ways should I use?

Weight per stitch when you know the stitches in the work, such as the rounds of an amigurumi. Weight per area for a blanket or a scarf measured in cm. Length per stitch for small amounts, where a kitchen scale is too rough.

Why is the answer a range?

Your gauge drifts over a large piece, so the calculator allows 10 % either way. The skeins to buy are worked from the upper end, so you will not run short.

The pattern already says how much yarn. What then?

Then convert the pattern's amount to your yarn by metres per skein: the yarn amount calculator for knitters does exactly that, with the same rule as CrochetBuddy.

Free crochet calculator

How much yarn will my crochet take?

Crochet takes very different amounts of yarn by stitch, so start from a piece of your own. Weigh it or pull it out, and get the yarn for the whole work.

Crochet a piece, such as the first rounds, count its stitches and weigh it.

Stitches in the swatch

The swatch weighs, in g

Stitches in the whole work

Meters per skein

Grams per skein

The pattern says how much? Convert it to your yarn.

Yarn amount

Buy 4 skeins

Grams: about 130–158 g
Meters: about 324–396 m
Skeins: about 2.6–3.2

±10 %, because the gauge varies over a large work. Leave a little left over rather than run short.

CrochetBuddy works this out on your phone, takes the stitches straight from your plan of rounds and keeps your yarn stash. It is with App Review now.

CrochetBuddy →

Coming soon to the App Store

How to work it out yourself

Example: a piece of 150 stitches weighs 12 g, the whole work has 1,800 stitches, and the ball band says 125 m per 50 g.

Grams per stitch: 12 ÷ 150 = 0.08 g.
The whole work: 12 × 1,800 ÷ 150 = 144 g. Multiply before you divide, so nothing is rounded on the way.
Gauge drifts over a large piece, so allow 10 % either way: 129.6 to 158.4 g.
Skeins to buy come from the upper end: 158.4 ÷ 50 = 3.168, rounded up to 4 skeins.

Buy 4 skeins Grams: about 130–158 g Meters: about 324–396 m Skeins: about 2.6–3.2

A kitchen scale too rough for a small piece? Crochet 20 stitches, pull them out and measure the yarn: the cm per stitch times the work's stitches gives the metres, and the ball band turns them into skeins.

Questions

Why do I need a swatch?: Because the yarn a crochet stitch takes depends on the stitch, the hook, the yarn and your hands. Rules of thumb are off by a lot, so the calculator only works from something you crocheted yourself.
Which of the three ways should I use?: Weight per stitch when you know the stitches in the work, such as the rounds of an amigurumi. Weight per area for a blanket or a scarf measured in cm. Length per stitch for small amounts, where a kitchen scale is too rough.
Why is the answer a range?: Your gauge drifts over a large piece, so the calculator allows 10 % either way. The skeins to buy are worked from the upper end, so you will not run short.
The pattern already says how much yarn. What then?: Then convert the pattern's amount to your yarn by metres per skein: the yarn amount calculator for knitters does exactly that, with the same rule as CrochetBuddy.

More crochet calculators

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