Free knitting math tools

Grade a knitting pattern with the math done right

Turn one sample size into a full size range with correct stitch counts and shaping. Free, runs in your browser.

Correct grading math Every size at once Printable PDF No sign-up

Why a tool, when a chatbot can do math?

Ask a general chatbot to grade a pattern and it will hand you confident, wrong numbers. It rounds stitch counts inconsistently across sizes, and it spaces shaping with a single "every N rows" that leaves you a stitch or two short by the top of the sleeve. Grading is fussy arithmetic where small errors compound, so it is the kind of job a purpose-built tool should own.

KnitGrader does the arithmetic the way a designer does it by hand. Stitch counts are gauge times your finished measurement, rounded to a whole stitch and to your pattern repeat. Shaping is spread with the even-interval method, so when the rows do not divide evenly you get a clean instruction like "increase 1 stitch at each end every 6 rows 5 times, then every 8 rows 3 times," and the count lands exactly on target. Every formula is checked against hand-worked examples.

At a gauge of 20 stitches per 10 cm, a finished chest of 100 cm comes to 200 stitches. A sleeve that grows from 44 to 60 stitches over 80 rows works out to an increase every 10 rows, eight times. The grader does this for every size at once.

Method: standard hand-knitting grading, gauge times measurement with even shaping distribution.
Guides

Learn the math behind the fit

01

How to grade a knitting pattern

Grading turns one knitted sample into a full size range. You keep the same gauge and proportions, then recompute the stitch cou...

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02

How to measure knitting gauge

Gauge is the number of stitches and rows over a set width and height, usually 10 cm or 4 in, worked in your pattern stitch and...

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03

Gauge swatch mistakes that ruin the fit

Most fit problems trace back to the swatch, not the knitting. A swatch that is too small, never blocked, or measured at the cur...

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04

When your gauge doesn't match the pattern

It is the most common message a knitter sends a designer: my gauge does not match the pattern. You have options, and none of th...

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05

Ease and sizing basics

Ease is the gap between your body measurement and the finished garment. It is the single number that decides whether a sweater...

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06

What is worsted weight yarn?

Worsted weight is the medium, all-purpose yarn most patterns are written for. It sits in the middle of the yarn range, knits to...

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07

Knitting vs crochet: what's the difference?

Knitting works a whole row of live loops on two needles; crochet finishes one stitch at a time with a hook. This guide compares...

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08

How to join knitting in the round

Joining in the round turns a flat row of cast-on stitches into a closed tube. Two things decide whether it works: the cast-on e...

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09

How to count rows in knitting

Rows are counted up one column of stitches, and the loops sitting on your needle are the last row you worked. The confusion sta...

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10

How to weave in ends in knitting

Weaving in an end means threading the yarn tail through the back of your fabric so it holds and can't be seen. Leave at least 4...

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Frequently asked questions

What is pattern grading?

Grading turns one knitted sample size into a full size range. It recomputes the stitch counts, row counts, and shaping for each size while keeping the same gauge and proportions, so every size fits the way the sample does.

Are these tools really free?

Yes. The pattern grading generator and the gauge calculator are free, run entirely in your browser, and need no sign-up. You can download a printable grade sheet PDF at no cost.

Is the grading math correct?

Yes. Stitch counts are gauge times the finished measurement rounded to a whole stitch, and shaping is distributed evenly so the count lands exactly on target. Every formula is checked against hand-worked examples, which is the part a generic chatbot gets wrong.

Do I need an account?

No account, no email, nothing to install. Open a tool, enter your numbers, and read the result. Your inputs stay in your browser.