How to Use the Paint Calculator
Enter the room's dimensions, the number of doors and windows to subtract, the paint's coverage rate, and the number of coats planned — the calculator computes the exact paint quantity needed, accounting for all of these factors rather than a rough room-size-only estimate.
The Paint Calculator accounts for the full calculation covered in the worked-example guide — here's what to enter.
Entering room dimensions and openings
Enter the room's wall dimensions and the number and approximate size of doors and windows — subtracting these from total wall area, as covered in the worked-example guide, avoids overestimating the paint actually needed.
Setting coverage rate and number of coats
Entering the specific paint product's stated coverage rate (rather than a generic default) and the planned number of coats gives a more accurate result — as covered in the running-out guide, an inaccurate coverage rate assumption is a common source of underestimating needed paint.