Yarn Yardage Calculator
Unravel the swatch and measure it. That figure knows your yarn, your tension and your cables — no chart does.
Measure your yarn per stitch
Unravel the swatch you knitted anyway and measure the yarn it used. This is the only figure that knows your yarn, your tension and your stitch pattern.
The project
Measure it, do not look it up
Every yarn quantity chart tells you what a sweater takes in some abstract yarn at some abstract tension. Yours is neither. The reliable method takes two minutes and needs no chart: knit the swatch you needed anyway, unravel it, and measure the yarn. Divide by the number of stitches and you have the length per stitch for your yarn, at your tension, in your stitch pattern.
That last part is the one charts cannot do at all. Cables and colourwork eat far more yarn than stocking stitch at the same gauge — a cable pulls the fabric in, so the same finished width holds far more stitches, and every one of them costs yarn. A stranded colourwork row carries a second strand across its whole length. No table indexed on yarn weight knows any of this, and a swatch knows all of it automatically.
The arithmetic afterwards is trivial: total stitches is width × stitch gauge × length × row gauge, and yarn is that times the length per stitch. A 15 per cent margin is added on top, because running short at the end of a garment means matching a dye lot that has gone.
Why the margin is not optional
Yarn is dyed in lots, and two balls of the same colour from different lots are visibly different in daylight — usually across a whole sleeve, where nobody can miss it. Shops rarely hold a lot for long. So the failure mode is not "buy another ball", it is "reknit the sleeve in a slightly wrong colour, or reknit both". Buying one ball more than the estimate costs a few pounds and removes the problem entirely; the leftover always finds a use.
Unravelling the swatch properly
- Count the stitches before you unravel, obviously — stitches across times rows down. Write it down; it is very annoying to have to reknit it.
- Measure the yarn without stretching it. Wool in particular will read several per cent long if you pull, and that error goes straight into the total.
- Wash and dry the swatch first if you are also measuring gauge from it, then unravel. Yarn that has relaxed gives both numbers correctly.
- Use the real stitch pattern. If half the garment is cabled and half is plain, measure two swatches and apply each to its own area.
- Do not skip the ribbing. Ribbing at a tighter gauge holds more stitches per inch than the body and uses proportionally more yarn.
How to use
- Count the stitches in your swatch, then unravel it and measure the yarn.
- Enter the project size and your gauge.
- Add the number of pieces — front, back, two sleeves.
- Buy the ball count shown, all from the same dye lot.
Frequently asked questions
How do I work out how much yarn a project needs?
Measure it rather than looking it up. Knit the swatch you needed for gauge anyway, count its stitches, unravel it and measure the yarn it used. Divide to get length per stitch, then multiply by the stitches in your project — width times stitch gauge times length times row gauge. It takes two minutes and beats any chart.
Why not use a yardage chart?
Because a chart tells you what a sweater takes in some abstract yarn at some abstract tension, and yours is neither. More importantly no chart indexed on yarn weight can know your stitch pattern, and stitch pattern changes yarn consumption dramatically.
How much more yarn do cables use?
Substantially more, and for a reason worth understanding: a cable pulls the fabric in, so the same finished width holds many more stitches, and every stitch costs yarn. The gauge you measure already reflects this, which is exactly why measuring your own swatch handles it automatically while a table cannot.
What about colourwork?
Stranded colourwork carries a second strand across the whole width of every row, so the total yarn is far more than the stitch count alone suggests — though split between colours. Swatch in the colourwork pattern and measure each colour separately if the proportions matter.
Why add a margin?
Because yarn is dyed in lots, and two balls of the same colour from different lots are visibly different in daylight — usually across a whole sleeve where nobody can miss it. Shops rarely hold a lot for long, so running short does not mean buying another ball, it means reknitting a sleeve in a slightly wrong colour. Fifteen per cent costs a few pounds and removes the problem.
How do I measure the unravelled yarn?
Without stretching it. Wind it round something of known circumference, or measure it in lengths against a table edge. Wool will read several per cent long if you pull as you measure, and that error goes straight into the total — in the direction that leaves you short.
Should I wash the swatch before unravelling it?
Yes, if you are also taking gauge from it — wash, dry, measure the gauge, then unravel and measure the yarn. Yarn that has relaxed gives both numbers correctly, and doing it in that order means one swatch does both jobs.
What if my project is not a rectangle?
Compute the rectangle that contains each piece and accept a small overestimate, or split the piece into rectangles and add them. A sleeve tapers, so its bounding rectangle overestimates by roughly the taper — which lands in the same place as the safety margin and does no harm.
Does ribbing use more yarn?
Yes. Ribbing sits at a tighter gauge than the body, so it holds more stitches per inch and uses proportionally more yarn for the same finished area. If a garment has deep ribbing at the hem and cuffs it is worth swatching the rib separately rather than assuming the body figure covers it.
How accurate is this?
As accurate as your swatch measurement, which is the point — it has no other assumptions in it. The arithmetic afterwards is exact. If the swatch is honest, washed, in the right stitch pattern and measured without stretching, the estimate will be close enough that the margin covers everything else.
What if I am substituting a different yarn?
Then this is the only method that will work, since the pattern's stated yardage applies to the yarn it was designed in. A different fibre at the same gauge can differ considerably in yardage per weight, so swatch in the yarn you will actually use and measure that.
Does this send anything anywhere?
No. Everything is calculated in your browser and nothing is stored or uploaded.
🔒 This tool runs entirely in your browser. Nothing you enter is uploaded, logged, or stored.