Search for what you need, or filter by craft. Everything works on a phone, and there's nothing to sign up for.
For the crafts with the most arithmetic.
Lay an unmarked needle or crochet hook on the screen and read its size in millimetres, US and UK — plus which yarn it suits.
Measure a needle → Knitting & crochetCompare your swatch to the pattern, see which way to change needles, and convert every stitch count to your own gauge.
Check my gauge → Knitting & crochetWrap the yarn, count the wraps against a true inch, and get the weight in every naming system with needle and hook sizes.
Identify my yarn → Knitting & crochetHow much yarn a project needs, how many balls to buy, whether your stash will stretch, and how to swap one yarn for another.
Work out my yarn → Knitting & crochetTurns "decrease 9 stitches evenly across the row" into an instruction you can follow stitch by stitch, for knitting or crochet.
Space my stitches → Knitting & crochetHead measurement and your gauge give the cast-on number, the length before the crown, and how much yarn it will take.
Size my hat → CrochetSquare counts, layout, finished size, yarn and a rough making time for any blanket — with a picture of how it will lay out.
Plan my blanket →Small things measured properly, right on the glass.
Match a bead to true-size circles, then count exactly how many you need for any bracelet or necklace, spacers included.
Size my beads → JewelleryFind the gauge of an unlabelled wire in AWG, British SWG and millimetres, with guidance on what each thickness is best for.
Identify my wire →Fabric sums, done before you cut.
Finished size from your stitch and fabric count, the fabric to cut with margins, and a comparison across every count.
Size my project → QuiltingStrips to cut, backing yardage with the seaming worked out, and which batting package to buy — before the fabric shop.
Work out my quilt →For the other corners of the craft cupboard.
Wax weight, fragrance oil and a starting wick for any container — including tapered jars and teacups.
Plan my candle → WreathsExact yardage for any bow, how many rolls to buy, and a sketch of the bow that updates as you change the design.
Plan my bow →Nothing matches that yet. Try a different word — or tell us what you were looking for and we'll see about building it.
Printable charts and gauges to keep by the chair, where a screen isn't welcome.
Every measuring tool has a paper companion — printed at true size, with a scale check so you can be sure your printer behaved. There's also a one-page cheat sheet gathering every number on the site, and a members' set of planning sheets.
We add tools one at a time, and the list is shaped by what people ask for. Currently in the queue: a mat board calculator for framing, a sock sizing guide, and a fabric yardage calculator for dressmaking.
If there's a sum you find yourself doing on the back of an envelope every time, we'd like to hear about it.
