How it works
wall area = width × height × wallspaint = area ÷ 350 sq ft per gallon (one coat)
- width
- wall width in feet
- height
- wall height in feet
- walls
- how many walls of this size
This assumes solid walls. For a truer paint estimate, subtract the area of large doors and windows, and double the paint for two coats.
Frequently asked questions
How do I calculate wall square footage?
Multiply width by height for one wall, then by the number of walls of that size.
How much paint for 384 sq ft?
About one gallon per coat, since a gallon covers roughly 350 sq ft.
Should I subtract doors and windows?
For a tight estimate, yes; for a rough one, leaving them in adds a small safety margin.
How many coats do I need?
Usually two for a colour change or new drywall, so double the paint.