Free Craft Calculators

The sums every maker ends up doing on the back of a pattern, done properly: how much yarn a crochet blanket, hat or sweater takes, how many granny squares a bed needs and the yarn for each colour, how many skeins of a substitute yarn to buy, how much epoxy to mix for a mold or tabletop, and how much wax and fragrance oil fill a batch of candle jars.

When it’s time to sell, the cost calculator adds up materials, time and overhead, the 3D printing calculator prices a print down to the electricity, and the pricing calculator works back through Etsy or card fees to a price that pays you. Everything works in inches or centimeters, ounces or grams, with no account and no limits.

• Shown working. Every calculator explains its formula on the page, and results update as you type.
• Your own tension counts. The yarn calculator can scale a weighed swatch to the whole project, and the granny square calculator can use a square you’ve already made.
• Fees solved exactly. Marketplace fees are a percentage of the sale, so the pricing calculator solves for the price rather than adding a percentage on top, and shows what you keep.
• Metric or imperial. Switch units at the top of any calculator and what you’ve typed is converted for you.

Yarn amounts by stitch and yarn weight are typical figures; your tension and fibre can change them by 20% or more, so weigh a swatch when it matters and buy from one dye lot. Marketplace fee presets are starting points: check them against your own statements. Your numbers are saved in your browser only.