About KitPine

Free calculators for the numbers behind home projects: paint, tile, concrete, lumber, stairs and roofs.

Updated October 19, 2026

What KitPine is

KitPine is a collection of small calculators for home improvement and DIY. Each one answers a question you have before a trip to the store or the lumber yard: how much paint to buy, how many boxes of tile, how many bags of concrete, how steep a roof is or how many steps a staircase needs.

The tools open quickly, work on phones as well as computers, and do one job each.

How we build each calculator

Every calculator puts its formula on the page with a worked example, so you can check the result by hand. When a calculator relies on a figure from the real world, such as how far a gallon of paint goes, the size of a drywall sheet or the steepest step a building code allows, we take it from the manufacturer, the standard or the code itself and list it under Sources with the date we checked it.

Where products differ, the calculator shows our default and lets you type the number printed on your own product instead.

Everything runs in your browser

Calculations happen on your own device. What you type is never sent to us or stored by us, and there is no account to create.

Eight language versions

KitPine is available in English for the United States, the United Kingdom and Australia, and in Japanese, German, French, Spanish and Italian. A tool only appears in a language once it has been written for that market, with local units, product sizes and building rules. Until then, the English version is listed with an EN label.

Estimates, not professional advice

The results are estimates for planning and shopping. For structural work, stairs, roofs and anything that needs a permit, your local building rules and a qualified professional come first.

Free to use

All tools are free. Ads pay for the running costs. They are clearly labelled, kept away from buttons and results, and cannot see anything you enter in a calculator. The privacy policy explains the details.

Spotted a wrong figure or a translation that reads oddly? Please get in touch.