Paint volume calculator

Estimate gallons or liters from paintable area, coats, labeled coverage, and allowance.

Direct answer

Multiply net paintable area by the number of coats, apply the chosen allowance, and divide by the product's labeled coverage per gallon or liter.

Interactive tool

Enter your measurements

Enter valid measurements and select Calculate.

Transfer these inputs to a new local editor project

Formula

Paint volume = area x coats x (1 + allowance) / labeled coverage per volume unit.

Worked example

500 sq ft at two coats and 400 sq ft per gallon needs 2.5 gallons before allowance; a 5% allowance gives 2.625 gallons before package selection.

Assumptions

The area is net of surfaces not painted.
Each coat uses the same labeled coverage.
The product coverage basis matches the selected unit system.

Caveats

Texture, porosity, color change, application, and product alter coverage.
Primer and specialty coatings are separate systems.
Follow product ventilation, preparation, disposal, and safety instructions.

Primary references

Volatile Organic Compounds' Impact on Indoor Air QualityU.S. Environmental Protection Agency; accessed 2026-08-02.

Understand and continue

Roofing, siding, flooring, paint, and finish quantities

Use surface-specific formulas and keep accessories, layers, exposure, and product instructions separate.

Read supporting guide

Three-bedroom family-home concept

A larger single-story program with shared living at the center and flexible bedroom or office use.

Open starting concept

Planning quantity, not construction directionThis calculator does not verify codes, specifications, structure, utilities, product suitability, purchasing, pricing, installation, or safety. Verify the result and all project decisions with qualified local professionals.