Paint Calculator
Enter your room to get the gallons of paint to buy, by coats and surface, plus an estimated cost.
How much paint do I need?
You'll need about
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| Paintable area | |
|---|---|
| Coverage needed (with coats) | |
| Estimated paint cost |
Estimate for walls (2 coats by default). Coverage assumes smooth, primed drywall; bare or textured walls absorb more — pick "Textured." Small doors/windows are left in as a cut-in buffer. Cost is an estimate (as of June 2026) — confirm the price of your chosen paint.
📘 New here? Read How much paint do I need?
How the paint estimate works
- Wall area = 2 × (length + width) × ceiling height. A 12 × 14 room at 8 ft = 416 ft².
- × coats — two coats is standard, so 416 × 2 = 832 ft² to cover.
- ÷ coverage — a gallon covers ~350 ft² of smooth drywall, so 832 ÷ 350 = 2.38 → 3 gallons (rounded up).
We leave small doors and windows in by default — that extra paint becomes your cut-in and touch-up buffer. Painting the ceiling adds length × width to the area.
Last updated: 2026-06-28.
Coverage from Sherwin-Williams and Behr guidance. Cost is a US-average estimate.