Measure once.
Buy the right amount.
22 fast calculators — rug size, square footage, paint, tile, concrete and more — every one showing its formula, plus 70+ step-by-step guides. No sign-up, nothing stored.
Most-used calculators
All 22 tools →Rug Size Calculator
Ideal & minimum rug size for any room and furniture.
SSquare Footage
Area of any room, including L-shapes.
PPaint Calculator
Exact gallons for walls, ceiling and trim.
TTile Calculator
How many tiles for a floor or wall, with waste.
CConcrete Calculator
Cubic yards, feet and bags for any slab.
FFlooring Calculator
Square feet, waste and cost for flooring.
Square Footage
Rectangles, L-shapes and odd rooms.
CCurtain Length
Floor, sill, apron or puddle looks.
WWallpaper
How many rolls for any room.
TTV Size
Screen size & viewing distance.
PPool Volume
Gallons your pool holds.
Paint
Gallons per room & coat.
TTile
Tiles with 10–15% waste.
FFlooring
Area, waste and cost.
CConcrete
Yards, feet and bags.
DDrywall
Sheets for any room.
MMulch
Cubic yards and bags.
GGravel
Cubic yards and tons.
LLumber
Board feet and cost.
CCarpet
Square feet and yards.
SSod
Pallets and rolls.
PPaver
Pavers for patio & walkway.
Fence
Posts, rails and pickets.
SStairs
Risers, treads and run.
DDeck
Boards, joists and cost.
RRoof
Squares & shingle bundles.
Why the numbers matter before you buy
Most home-material mistakes aren't about taste — they're about math. A rug a few inches too small under a king bed leaves an awkward gap; one gallon of paint too little means a second trip and a visible seam; a few bags of concrete short at the end of a pour is the last thing you want.
Every tool shows its formula and a worked example, so the number isn't a black box. Measure twice, add 10% for waste, and verify with your supplier — start with a calculator, then check the matching guide for the full method.
Popular guides
All guides →Rug size by bed
King, queen, full, twin — exact rug sizes and placement for every bed type.
Read the guide →How to measure for a rug
A simple 6-step method to measure any room and pick a rug that fits.
Read the guide →How much paint do I need?
Room-by-room gallons chart, the coverage formula, and common mistakes.
Read the guide →How much concrete for a slab?
Cubic yards to bags, depth by use, and a worked example.
Read the guide →Square footage of a house
How to calculate any room or whole house, and what counts in a listing.
Read the guide →See all guides
Carpet vs hardwood, shingles, fence cost, and more how-to articles.
Browse all guides →Ready to buy without over-ordering?
Free, no sign-up, US units. Pick a calculator, get the exact amount, and check the guide before you spend.
Start with a calculator