Work out how much material your job takes
Ten calculators for common home improvement materials. Each gives you the quantity, the other items you'll need to buy, and the source for every figure.
Every number has a source
Each calculator shows the formula, the constants it uses, where each came from, and the date it was last checked. The site will not publish a page if a price gets stale or its sources go missing.
How these work
The whole job, not one number
Quantities and a cost range for the whole job, not just the headline figure. Tile gives you thinset and grout; drywall gives you mud, tape, and screws; a fence gives you the concrete for every post hole.
Codes and manufacturer rules
Where a code or a manufacturer's standard governs the answer, the page says so. A ceiling framed at 24 inches needs 5/8 inch board. A fence around a pool has to meet safety rules for height, gaps, and gates. A shower needs waterproofing on one side of the backer board, not both.
Where people get it wrong
Carpet is billed at the roll's full width, so a room just over 12 feet wide takes 71% more than its area suggests. A post hole needs less concrete than its own volume, because the post displaces it. A gallon covers 350 square feet in theory and less on your wall.
How to check our work
Every constant and price on this site carries a source and the date it was checked, and the site checks both before it publishes. A page with prices older than 180 days, or with its sources missing, does not go live. Where a trade group publishes a number, we use it: PennDOT for aggregate densities, the CRI for carpet, the TCNA for shower waterproofing, and the IRC and NWFA for how materials are installed. Where no such source exists, the page says the figure is a retail listing.
- Figures come from manufacturer data sheets, not from other calculators.
- When sources disagree, the page shows the range.
- Our own estimates are labeled as estimates.
- A number that gets repeated online but has no source is called out and left out.
Read more on the about page, or see the disclosure of how the site is paid for.
What these calculators are not
They are estimating tools. Each page tells you to confirm the figure with your supplier before you order, because aggregate weight varies by source, coverage varies by product, and a bed edge is never as straight as it looked. They are also not a substitute for a licensed contractor where the work needs one, or for your local building department where the work is inspected.
If a figure here disagrees with your supplier's, theirs governs.