Paint Calculatorv1.0.0

Use these coverage rates to estimate paint needs and plan purchases with confidence. Adjust for rough surfaces, porous materials, or textured finishes.

• Interior coverage: One gallon (3.8 liters) covers about 400 square feet (37 square meters).
• Exterior coverage: One gallon (3.8 liters) covers about 350 square feet (33 square meters).

Round up to the nearest gallon or liter to ensure complete coverage and touch-up capacity. Expect differences based on surface condition, primer use, paint quality, sprayer or roller application, and humidity.

Set up your project quickly and get accurate paint estimates for interior or exterior work. Follow these steps to capture walls, ceilings, openings, trim, and the number of coats.

• Select Interior or Exterior to apply the correct coverage rate.
• Choose Imperial or Metric units to match your measurements.
• Enter each wall’s width and height; enable Peak if the wall has a gable and enter the rise.
• Add Windows and Doors to subtract openings from the paintable area.
• Enable Trim to include baseboards, crown, and custom runs that require paint.
• Click + Add Ceiling and enter length and width for any ceilings you plan to paint.
• Set the Number of Coats to reflect primer, base, or finish coats.
• Press Calculate to view total surface area and recommended paint in gallons, quarts, or liters.

Formulas: Wall area uses Area = Width × Height; peak area uses 0.5 × Width × Rise. Paint required equals Total Area ÷ Coverage Rate, multiplied by the number of coats.

Plan projects, control costs, and reduce waste by estimating paint accurately for real situations. Adjust settings to compare scenarios and choose the best approach.

• Estimate paint for a full interior room that includes multiple walls and a ceiling.
• Calculate paint for an exterior façade while subtracting doors and windows.
• Include trim, baseboards, chair rails, and crown molding in the total area.
• Compare single-coat, two-coat, and primer-plus-finish plans to budget materials.
• Switch between Imperial and Metric units to align with local standards or supplier specs.

Model common rooms to validate your plan before you buy paint. Use these examples as starting points and adjust to match your space.

• Bedroom example: Enter four walls at 12 ft × 9 ft, add one 3 ft × 5 ft window and one 3 ft × 7 ft door, set two coats, and add a 12 ft × 12 ft ceiling.
• Living room with gable: Enter two standard walls and two walls with a peak; set peak rise to capture the triangular area accurately; add larger window openings and crown molding.
• Exterior accent wall: Switch to Exterior, enter one large wall, subtract two windows, set one coat for primer and one for finish, and review total gallons with rounding.

Yes. Higher-quality paints and certain sheens can cover differently. Use the provided rates as a baseline and add a safety margin for textured or porous surfaces.

Yes. Increase the number of coats when your plan includes primer or specialty undercoats. This approach keeps totals realistic for new drywall or drastic color changes.

Break irregular ceilings into rectangles you can measure and add them as separate ceilings. For complex shapes, approximate with multiple rectangles to capture total area.