Free Home Improvement Calculators for Every Project

How Much Paint Do I Need?

The amount of paint required depends on the surface area you are painting, the number of coats, the paint's coverage rate and the condition of the surface.

For walls, the basic calculation starts with the room's perimeter and wall height:
Wall Area = 2 x (Room Length + Room Width) x Wall Height

If you are painting the ceiling, use Ceiling Area = Room Length x Room Width. Then estimate paint with Paint Needed = Paintable Area / Coverage per Coat x Number of Coats.

Actual paint requirements can differ because coverage depends on product, surface texture, porosity, application method and other project conditions.

How to Use the Paint Calculator

1. Enter your room measurements.
2. Add doors and windows so their areas can be deducted.
3. Choose the number of coats you plan to apply.
4. Add ceiling measurements if you are painting the ceiling.
5. Enter the coverage stated by your paint manufacturer.
6. Add a waste allowance for practical variation.
7. Review your paint estimate and paintable area.

Calculate Paint for Different Painting Projects

Interior Tailor can be used as a starting point for estimating paint requirements for:

• Bedrooms, living rooms, dining rooms and offices
• Hallways, ceilings and interior walls
• Multiple-wall projects and other measurable surfaces

For unusual room shapes or surfaces, divide the area into smaller measurable sections and calculate each section separately.

Explore Paint Colors Before You Start Painting

Paint Color Mixing

Use the Color Mixing Lab to enter a target HEX color and explore an estimated digital mixing recipe. It is a planning tool, not an exact manufacturer formula.

Room Color Visualization

Use the Room Color Visualizer to preview a selected color in a room environment and explore different lighting conditions.