Paint calculator
The right paint. The right amount.
Plan paint, primer and purchase quantities for one room or a whole project. Enter your measurements, adjust the assumptions, and leave with a shopping plan.
Buy with confidence.Transparent formulas. Your prices.
Saved on your device.
From wall measurements to whole cans
Wall area is the room perimeter multiplied by wall height. Doors, windows and other unpainted areas are deducted. Add a ceiling as a separate surface to keep its paint purchase distinct.
Already know the net area? Use the paint coverage calculator to work from area or from paint you already have.
A worked example
A 12 × 10 ft room with 8 ft walls has 352 sq ft of wall. One 21 sq ft door and two 12 sq ft windows leave 307 sq ft. Two coats at 350 sq ft/gal plus 10% extra need 1.9297 US gallons. Buy two gallons.
Check before checkout
Coverage varies by product and surface. Use the label value, confirm coats and check the suggested container sizes are sold in your chosen finish. Do not combine different colours just to reduce rounding.
Questions worth answering before you paint
Does this include doors and trim?
Doors and windows are deducted as openings. To paint doors or trim, add a custom-area surface with its measured paintable area and a separate paint group. Include all faces you intend to paint.
Can I save without creating an account?
Yes. Save on this device stores one project locally. Download project keeps a portable file. Neither creates an online account.
Is this a guaranteed quote?
No. It estimates quantities and a budget from your inputs. Product performance, preparation and local prices can change the outcome.