Paint Calculator

Calculate exactly how much paint you need for your walls, rooms, or any surface. Get accurate estimates with cost calculations to plan your painting project.

Paint Calculator

How to Use the Paint Calculator

  1. Choose Calculation Type: Select room, individual walls, or enter known surface area
  2. Enter Dimensions: Input length, width, and height measurements in feet
  3. Specify Coats: Choose the number of paint coats (2 coats recommended for best coverage)
  4. Count Openings: Enter the number of doors and windows to subtract from surface area
  5. Select Coverage: Choose paint coverage based on surface texture and paint quality
  6. Review Results: See paint needed, cost estimates, and primer requirements

Examples and Use Cases

Common Room Sizes

12×10 ft room, 8 ft ceiling
~1 gallon for 2 coats
16×12 ft living room
~1.5 gallons for 2 coats
20×15 ft master bedroom
~2 gallons for 2 coats

Coverage Guidelines

Smooth Surfaces
400 sq ft per gallon - new drywall, smooth walls
Standard Coverage
350 sq ft per gallon - most interior walls
Rough/Textured
300 sq ft per gallon - textured, stucco, brick

Frequently Asked Questions

How accurate is this paint calculator?

Our calculator provides estimates within 10-15% accuracy for most projects. Actual paint needed may vary based on application method, surface porosity, and paint viscosity.

Should I buy exactly the calculated amount?

It's recommended to buy 10-20% extra paint for touch-ups and future maintenance. Our calculator already rounds up to the next gallon/quart for convenience.

Do I need primer for every paint job?

Primer is needed for bare surfaces, dramatic color changes, or when painting over stains. For similar colors over existing paint, primer may not be necessary.

How many coats of paint should I apply?

Two coats are recommended for best coverage and durability. Light colors over dark surfaces may need a third coat.