Guide · Home Improvement

How Much Paint for a 12×12 Room?

How much paint for a 12×12 room? With 8 ft ceilings, one door, two windows, and two coats on the walls only, you need about 1.90 gallons exact—so buy 2 gallons at a planning rate of ~350 sq ft per gallon per coat. Use the free Paint Calculator to change coats, openings, or add the ceiling.

Reviewed / updated August 2026

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Quick answer

For a typical 12×12 ft bedroom:

| Input | Value | | --- | --- | | Ceiling height | 8 ft | | Coats | 2 | | Doors / windows | 1 / 2 | | Ceiling painted? | No |

Buy 2 gallons of finish paint (planning estimate).

Run the live math in the Paint Calculator—defaults match this example.

The math

  1. Walls = 2 × (12 + 12) × 8 = 384 sq ft
  2. Openings = 21 + 30 = 51 sq ft
  3. Paintable = 384 − 51 = 333 sq ft
  4. Exact = (333 × 2) ÷ 350 ≈ 1.90 gal
  5. Buy = 2 gal

Full method and related materials: How to estimate materials for any home project. Category hub: Home Improvement calculators.

Draft notes

  • Dark-to-light color changes may need a third coat.
  • Keep a quart for touch-ups after furniture moves.
  • Content status: draft stub — expand with more room sizes as the cluster grows.

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Frequently asked questions

How many gallons of paint for a 12x12 room?

For walls only at 8 ft height with one door, two windows, and two coats, plan on 2 gallons after rounding up from about 1.90 gallons exact. Including the ceiling or a third coat increases the total.

Does a 12x12 room need primer too?

Primer is separate from finish paint. Bare drywall, stains, or drastic color changes often need primer first. Size finish coats with the Paint Calculator, then follow the primer can for coverage.