Free woodworking maths
Woodworking and Carpentry Maths Toolkit
Fast, plain-English calculators and guides for estimating lumber/timber, board feet, sheets, decks, stairs, rafters, miters, wood weight, costs, and cut lists.
Plan material quantities with less guesswork
This site is for DIY builders, woodworkers, carpenters, contractors, furniture makers, and anyone who needs quick project maths before buying boards, panels, or hardware. The tools are free and focused on practical estimating, not accounts, subscriptions, or paywalls.
What you can estimate
- Board feet, linear feet, and lumber/timber cost comparisons.
- Sheet goods, deck boards, stair stringers, rafters, and miters.
- Cut lists, wood weight, waste allowance, and early buying quantities.
Popular calculators
Start with the core project-planning tools.
Board Foot Calculator
Estimate lumber/timber volume from thickness, width, length, and quantity. Use it when comparing boards, planning material purchases, or checking rough stock requirements before a project.
Open pageLumber/Timber Cost Calculator
Estimate lumber/timber material cost from quantity, unit price, waste, and optional extra allowance. Use it when comparing supplier prices, budgeting a project, or checking whether a material order fits your plan.
Open pageNominal to Actual Lumber Size Calculator
Compare common nominal lumber/timber names with approximate actual finished sizes. Use it before layout, joinery, cut lists, or material estimates so planned parts match the stock you can actually buy.
Open pageSheet Goods Calculator
Estimate plywood, MDF, OSB, and panel quantities for cabinets, furniture, and site work.
Open pageDeck Board Calculator
Estimate deck board quantities from deck size, board width, gaps, stock length, layout direction, waste, and optional material costs.
Open pageFence Board Calculator
Estimate fence boards or pickets, posts, rails, waste, and optional material cost.
Open pagePractical guides
Clear explanations before you open a calculator.
How to Calculate Board Feet
Learn the board foot formula and how to use it when buying rough lumber or timber.
Open pageBoard Feet vs Linear Feet
Understand the difference between volume pricing and length pricing for wood projects.
Open pageNominal vs Actual Lumber Sizes
Learn why a 2x4 is not usually 2 inches by 4 inches and how to plan with actual sizes.
Open pageHow to Estimate Sheet Goods
Estimate plywood, MDF, OSB, and panel quantities without under-buying.
Open page