Measure twice, buy once
Material and project calculators for DIYers and contractors — know how much to buy before you head to the store.
⭐ Featured tools
🆕 New tools
📚 Guides
📐 Measure & Area
Square Footage Calculator
Calculate square footage for up to four rectangular rooms or areas and get the total in square feet, square yards and square meters.
Flooring Calculator
Calculate how much laminate, vinyl or hardwood flooring to buy, including waste, and how many boxes you need.
Tile Calculator
Calculate how many floor or wall tiles you need from the area and tile size, with waste and boxes.
Paint Calculator
Estimate how many gallons of paint you need for a room from wall length, height, doors, windows, coats and coverage.
🧱 Outdoor & Garden
Concrete Calculator
Calculate how much concrete you need for a slab, patio or footing in cubic feet, cubic yards and 40, 60 or 80 lb bags.
Mulch Calculator
Find how much mulch you need in cubic yards and 2 or 3 cubic foot bags from the bed size and depth.
Gravel Calculator
Estimate how much gravel, crushed stone or sand you need in cubic yards and tons for a driveway, path or base.
🏠 Building
Roofing Calculator
Estimate roof area, roofing squares and bundles of shingles from the house footprint and roof pitch.
Stair Calculator
Calculate the number of stairs, riser height, tread run, stair angle and stringer length from the total rise.
Board Foot Calculator
Calculate board feet for lumber from thickness, width, length and quantity, plus the total cost at a price per board foot.
❄️ Energy
BTU Calculator
Find the right air conditioner size in BTU for a room from its area, sun exposure, number of people and whether it is a kitchen.
Electricity Cost Calculator
Calculate how much electricity an appliance uses and what it costs per day, month and year from its watts, hours of use and your rate.
Frequently Asked Questions
Do I need to sign up or log in?
No. Every calculator works instantly without an account. A free account is only needed if you want to save results (up to 30) and see them later.
Is my data stored anywhere?
The numbers and dates you type are calculated in your browser and are not sent to us. We keep basic visit statistics (page visited, IP address, browser, time) and, if you save a result, that saved result in your account. The AI Assistant sends your question to an AI provider to answer it.
Are the results exact?
Date and age maths is exact. Money, tax and health tools are estimates based on published formulas and official tables, and are not professional advice.