Paint Calculator

How much paint you need — before you buy the wrong amount.

Wall area to paint:

Gallons needed:

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How to use this calculator

Enter room dimensions, wall height, coats of paint, and the window and door areas, then press Calculate. The wall area to paint and gallons needed are shown.

What the result means

The gallon count is what you'll actually need including multiple coats. It's cheaper to have a little extra than to chase a matching dye lot mid-project.

Frequently asked questions

How many coats do I need?

Most colors need two coats for even coverage, especially when painting a light color over dark.

Does this include primer?

No — add primer separately for bare drywall, stains or major color changes.