How do you calculate wall paint square footage?

Multiply wall height by width in feet. For a 12×12 room with 8ft ceiling, multiply perimeter (48ft) by height (8ft) = 384 sq ft. Subtract doors (20 sq ft each) and windows (15 sq ft each). One gallon covers about 400 sq ft.

How much paint do I need for square feet?

One gallon typically covers 350-400 square feet with one coat. For two coats, divide the area by 200. Add 10% for wastage.

Do I need to subtract windows and doors?

Yes, subtract approximately 20 square feet for each door and 15 square feet for each window from your total wall area for accurate paint calculations.

How many coats of paint do I need?

Most paint jobs require two coats for optimal coverage. When painting over dark colors or using bright/deep colors, you may need three coats. Always use primer on bare drywall or when making dramatic color changes.

What's the coverage rate for different paint types?

Standard paint covers 350-400 square feet, economy paint covers 250-300 square feet, and premium paint covers 400-450 square feet per gallons.

How do I calculate paint for irregular walls?

Break irregular walls into rectangular sections, calculate each section in square feet, then add them together. Add 10% extra for irregularities.

Wall Paint Calculator Square Feet | Free Paint Coverage Calculator

Calculate exact wall paint square footage instantly. Enter room dimensions below for precise paint requirements in square feet. Includes adjustments for doors, windows, and multiple coats. Perfect for 12×12 rooms and standard wall sizes.

Select your preferred unit system:

Select Room Shape

Rectangular Room

L-Shaped Room

Room with Bay

Room with Alcove

Room Dimensions

Imperial (ft)

A simple rectangular room with four walls

Room Dimensions

Length

Width

Height

Measurement Tips

Measure each dimension at multiple points and use the largest measurement for accurate results.

Loading specifications...

Total Area

0sq ft

Paint Required

0gallons

For 2 coats of standard paint

Primer Required

0gallons

For one coat of primer

Estimated Time

0 hours

Approximate time to complete

Pro Tips

Extra Coverage

Add 10% extra paint for touch-ups

Drying Time

Allow paint to dry between coats

Quality Check

Inspect surfaces between coats