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Exterior Paint Calculator

Add rectangular elevations and triangular gables, then subtract windows and doors before counting paint.

Your measurements

Editable example

Use the unit on each label. You can also type feet and inches with ft and in, or the marks on your tape measure.

Elevation 1
Package sizes, prices and materials

Example: replace these measurements

Your material list

2 1-gallon paint cans

320 sq ft measured

Shopping list & save options
Paintable area
320 sq ft
Area across all coats
640 sq ft
Paint before can rounding
1.6 US gal
Paint volume before rounding
6.06 liters
Surface 1
320 sq ft
Paint subtotal
Add your price

Width 30 ftWall 9 ftGable 6 ft
Wall elevation with a triangular gable above the dashed line. Openings are subtracted separately.

The calculation

  1. Surface area: 320 sq ft
  2. ceil(320 × 2 × (1 + 0/100) ÷ 400) = 2

Material price trends, separate from your quote

These U.S. producer indexes track material prices over time. They are not store prices, labor rates or local installed costs. We do not use them to increase a historical project median.

Prepared paint

+5.9% from August 2025 to August 2026. Latest observation is preliminary and may be revised.

BLS producer index, not seasonally adjusted
PeriodIndex level, not dollars
August 2025430.843
August 2026456.224

U.S. Bureau of Labor Statistics · Updated . Use your quoted unit price in the material calculator; delivery, tax, preparation and labor remain separate.

Before ordering, use the paint measurement, coats & label inputs guide to check the inputs and take the right questions to the supplier. Choose another calculator.

How to plan the quantity

Each elevation combines a rectangle and an optional triangular gable above it. The gable rise is its height above the rectangle. Set that rise to zero for a plain wall.

Subtract windows and doors measured in square feet. Add another elevation for a different wall, and keep trim or a different color on a separate list.

The calculation multiplies the net area by your coats and divides by product coverage. Rough or porous siding can need a different coverage input from smooth trim.

Before you order

  • Access equipment, cleaning, scraping, repairs and lead-safe work can matter more than the paint quantity. This list does not price those tasks.
  • Use the product’s guidance for the substrate and application method. A geometric area is not a promise of real-world coverage.