Free woodworking calculators
Five calculators for the arithmetic that sits between a design and a pile of timber: board feet, plywood sheets, shelf spacing, saw kerf and miter angles. Metric and imperial, results as you type.
No account, no email, no limits. Every one runs entirely in your browser — the numbers never leave your device, and the maths is the same deterministic arithmetic every time, not an estimate from a model.
Material & quantity
Work out how much stock to buy before you go to the timber yard.
Layout & spacing
Position parts inside a carcass and get the openings right.
Cutting & angles
Set the saw correctly and account for what the blade removes.
Where a calculator stops
Each of these answers one question in isolation. That is genuinely useful at the timber yard or standing at the saw, and for a lot of jobs it is all you need.
A complete project is a different problem. The shelf spacing depends on the carcass height, which depends on the material thickness; the shelf length depends on whether you are housing it in a dado, which changes the cut list; the sheet count depends on how those parts actually nest, not on their total area. Change one dimension and every one of those moves. That is the part these five tools cannot do for you, because each only sees its own inputs.
PlankCAD works the whole job out together — materials, hardware, labour, waste and shop overhead in one estimate, with a true gross-margin target applied to the total rather than guessed at per line.
Common questions
Yes, and there is no account, no email and no limit on how many times you use them. They run entirely in your browser, so nothing you type is sent anywhere. The arithmetic behind them is not proprietary — it is arithmetic most shops were never taught.
Yes. Each calculator accepts the units woodworkers actually use for that job — board feet and quarter-inch stock where that is the convention, millimetres for sheet layout — and converts internally rather than making you convert first.
A calculator answers one question in isolation: how many board feet, how many sheets, what miter angle. It cannot tell you what to charge, because that needs materials, hardware, labour hours, waste, overhead and a target margin considered together, and it cannot check that a part actually fits the sheet you own. That is what the estimator and the cut optimizer are for.
The formulas are deterministic — the same inputs always produce the same answer, with no rounding hidden between steps. What they cannot know is whether your inputs are right: a board-foot figure is only as good as the thickness you measured, and a sheet count assumes the offcuts are usable. Check a result you can verify by hand before trusting it on a job.
You can use the numbers, but a calculator output is not a quote. A defensible quote shows the cost basis, the waste and overhead applied, and the margin taken, so you can answer a customer who asks how you got there. The free estimator produces that as a PDF.
Build your first estimate free.
No credit card required. Price the job, save the draft, and export the customer quote.
Deterministic Estimate Math · Your Quotes On Your Account · No Hidden Fees