Support

Questions about Paint Calculator? We’re happy to help.

Contact

Email matt@mattchapman.net. We typically respond within a few business days.

System requirements

iPhone or iPad running iOS 17.0 or later
No account or internet required for the estimate (ads use a connection when shown)

Getting started

Enter length, width, and height for the room.
Turn ceiling on or off. Add doors and windows so they come off the walls.
Set finish and primer coats. Match coverage to the can if the label differs from 350 / 250 sq ft per gallon.
Buy the whole gallons shown for finish and primer. The exact gallons and square-foot breakdown are underneath.

Common questions

Why does it round up?

Paint is sold in whole gallons. The App shows the exact amount and the cans to buy so you do not come up short.

What if I am not priming?

Set primer coats to 0. Finish paint is unchanged.

Doors and windows

The App subtracts 21 sq ft per door and 15 sq ft per window from the walls. That is a standard opening allowance, not a measured door or window.

The estimate seems high or low

Check the can. Coverage varies by product, surface, and color change. Adjust finish and primer sq ft/gal to match the label. Two coats is typical for a color change; one coat is sometimes enough for the same color.

The App is free and supported by a banner. In some regions you will see a consent screen on first launch. That is required for advertising. Room numbers are not sent to us with those ads.