Free calculators for home & building projects
Work out how much material you need, how many bags to buy and what it will cost, before you go to the store.
How it works
1. Measure
Grab a tape measure and note the length, width and depth of your project. Feet, inches or meters all work.
2. Calculate
Type the numbers in. You see the answer instantly, plus the bags, pieces or tons to buy and an optional cost estimate.
3. Buy with confidence
Copy the result for your supplier. Every page shows the formula and a worked example, so you can check the math yourself.
Browse by project
Roofing & Siding
Roof pitch, rafters, trusses and siding materials.
Coming soon
Carpentry & Lumber
Board feet, framing, lumber and trim work.
Coming soon
Measurement
Volume and area conversions every project needs.
1 calculator
Landscaping & Paving
Asphalt, sand, gravel and stone for yards and driveways.
Coming soon
Built for real projects, not math class
Most home projects go wrong at the store, not on site. You buy six bags when you needed nine, or a full yard of gravel when half would have done. CalcWall exists to fix that. Each calculator answers the question you actually have, such as “how many bags?” or “how many boards?”, not just a raw number.
Whether you are filling a raised bed, framing a shed wall or pricing a new driveway, you get the quantity, a sensible allowance for waste and, if you add a price, a cost estimate. Every calculator works on your phone in the store aisle, runs entirely in your browser and never asks you to sign up.
Pros are welcome too: our pages list the exact conversion factors and assumptions behind every result, so estimators and contractors can check the numbers before they go into a quote. See how we calculate.