Sumwise

Free · No sign-up · Works on your phone

Calculators that show their working.

Roofing and decking numbers, marketplace fees and creator payouts. Enter your figures, get the answer and see exactly how it was worked out.

Home & Trade

Home & Trade Calculators

Material quantities and measurements for roofing, decking, concrete, fencing and paint.

Seller Fees

Seller Fee Calculators

See what each marketplace takes and what you actually keep on a sale.

Creator Tools

Creator Payout Calculators

Turn bits and subs into the money that actually reaches you.

How we build every calculator

Each tool shows the formula it uses with your numbers filled in, a worked example, and the source for any fee or rate. Fee tables are checked against the platform's own published rates and the check date is printed on the page. More about how we work.

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