Free crochet calculators and tools
The crochet calculators handle the arithmetic that stalls projects: how many stitches to chain for a given width, how much yarn a blanket needs, how to spread increases evenly across a round, and which hook converts to which size. Each tool shows the formula it uses so you can check the result.
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Gauge Calculator
A crochet gauge calculator compares the stitches and rows you get in a 4-inch swatch with the gauge a pattern asks for.
Row Counter
An online crochet row counter keeps track of rows or rounds as you work.
Yarn Yardage Calculator
A yarn yardage calculator estimates how much yarn a crochet project needs from a swatch.
Temperature Blanket Generator
A temperature blanket generator assigns a yarn colour to each temperature range and turns a list of daily temperatures into a row-by-row plan.
C2C Graph Maker
A C2C graph maker lets you draw a corner-to-corner crochet design on a grid, one tile per square.
Increase / Decrease Calculator
An increase and decrease calculator spreads extra or fewer stitches evenly across a crochet row or round.
Hat Size Calculator
A crochet hat size calculator turns a head circumference into the hat circumference, flat crown diameter and height to work.
Blanket Size Calculator
A crochet blanket size calculator turns a standard blanket size, from lovey to king, into a foundation chain and row count for your gauge.
Hook Size Converter
A crochet hook size converter translates between metric millimetres, US letter-number sizes and old UK numbers.
Stitch Multiple Calculator
A stitch multiple calculator finds a starting chain that fits a stitch pattern written as a multiple, such as a multiple of 4 plus 2.
US ⇄ UK Pattern Translator
A US to UK crochet translator rewrites pattern text between the two terminology systems.
Striped Pattern Generator
A crochet stripe generator plans the colour order and height of stripes for a blanket, scarf or bag.
Yarn Substitution Finder
A yarn substitution finder checks whether a different yarn can replace the one a pattern lists.
Granny Square Layout Planner
A granny square layout planner works out how many squares a blanket needs and arranges colours so no two matching squares touch.
Color Palette Generator
A crochet colour palette generator builds a five-colour yarn palette from one colour you already own.
Skein to Yardage Converter
A skein to yardage converter turns skeins into total yards, metres and grams using the numbers on the yarn label.
Amigurumi Sizing Calculator
An amigurumi sizing calculator predicts how big a toy will be with a different hook, and plans a ball of any diameter.
Project Time Estimator
A crochet project time estimator predicts how long a piece will take from its total stitches and your speed.
Yarn Cost Calculator
A yarn cost calculator works out what a crochet project costs in yarn.
Chart Symbol Decoder
A crochet chart symbol decoder explains what each symbol in a crochet diagram means.
How do you calculate how many stitches to chain?
Multiply the width you want by the number of stitches per inch from your gauge swatch, then add the turning chain for your stitch. For example, a 40-inch width at 3.5 stitches per inch needs 140 stitches.
If the pattern uses a stitch repeat, round to the nearest multiple of the repeat plus any extra stitches the pattern specifies. The stitch multiple calculator does this rounding for you.
Which crochet calculator do you need?
Use the gauge calculator to convert a swatch into stitches and rows per inch, then the blanket size, hat size or yarn yardage calculators to plan dimensions and how much yarn to buy. The stitch multiple calculator rounds your starting chain to fit a stitch repeat, and the increase and decrease calculator spreads shaping evenly across a row or round.
Planning tools include a temperature blanket generator, striped pattern generator, colour palette generator, granny square layout planner and corner-to-corner graph maker. Reference tools convert hook sizes, translate US and UK abbreviations and decode chart symbols, and the row counter keeps your place. Every tool runs in your browser and explains the formula behind its result.
Frequently asked questions
Are the crochet calculators free?
Yes. Every tool is free and runs in your browser; nothing you enter is stored on our servers.