DIY Home Calculators - Measure Twice, Buy Once
Free calculators for the jobs homeowners actually do: flooring, paint, tile, concrete, mulch and more. Every tool shows its formula and a worked example, works in feet or meters, and needs no signup.
Start with the Project Planner
Planning more than one job? Enter your rooms once, tick flooring and paint per room, and get one combined shopping list with total boxes, gallons and cost. It is the fastest way to plan a room refresh - and it prints.
All calculators
Project Planner
Enter rooms once, tick flooring and paint, and get one combined printable shopping list.
Flooring Calculator
Boxes, square feet and cost for one room or the whole house, with waste included.
Paint Calculator
Gallons or liters for walls and ceilings, room by room, with doors and windows subtracted.
Tile Calculator
Tiles, boxes and a grout estimate, including the grout gap in the count.
Concrete Calculator
Bags or ready-mix yards for slabs, footings and post holes, with both costs.
Mulch Calculator
Bags vs bulk yards for mulch, soil, gravel and stone, with a price comparison.
Drywall Calculator
Sheets plus screws, tape and compound for a room, ceiling included if you want it.
Wallpaper Calculator
Rolls calculated from strips and pattern repeat, the way wallpaper actually works.
Deck Calculator
Deck boards, linear feet, joists and screws from board width and gap.
Grout Calculator
Pounds and bags of grout by tile size, joint width and tile thickness.
Square Footage Calculator
Total area for rectangles, circles and triangles, in square feet and meters.
Built for one store trip
Most material mistakes are not math mistakes - they are list mistakes. A box of flooring forgotten here, a gallon of paint short there, and the project stops for a second trip. These calculators are built around how material is actually sold: whole boxes, whole gallons, whole bags and whole rolls, with sensible waste allowances and the full working shown so you can sanity-check every number.
Every page includes the formula, a worked example you can verify with a pocket calculator, the assumptions behind the defaults, and answers to the questions homeowners ask most. If a number looks off, you can see exactly why.
Frequently asked questions
Are these calculators free?
Yes, completely free, with no signup. Every calculation runs in your browser, so your measurements never leave your device.
What makes this site different from other calculator sites?
The Project Planner. Other sites give you one calculator at a time, so you re-measure the same room for flooring, then again for paint. Here you enter each room once and get one combined, printable shopping list with one total cost.
How accurate are the results?
The math is exact for the numbers you enter, and every calculator shows its formula and a worked example. Real jobs vary with product coverage, cuts and site conditions, so treat results as a careful planning estimate and check the label on your product.