Paint · 6 min read

How to Estimate Paint for a Room

Wall area, coats, coverage rates, and practical buying tips — plus a visual paint calculator to see liters and cans.

Use with our Paint Calculator.

Paint estimates hinge on surface area, how many coats you plan, and the coverage printed on the can (m² per liter or sq ft per gallon). Textured or porous walls need more product than smooth primed drywall.

Simple estimation formula

Paint volume

Liters ≈ (wall area × number of coats) ÷ coverage per liter

Bedroom 4 m × 2.5 m, 2 coats, 10 m²/L

Area = 10 m². Total painted area = 20 m². Liters = 20 ÷ 10 = 2 L — often one large can plus touch-up reserve.

How many coats?

  • New drywall: primer + 2 finish coats
  • Repaint similar color: often 2 coats
  • Dark over light: may need 3 coats or tinted primer
  • Exterior: manufacturer minimum coats for warranty

Open paint calculator

Enter wall size, coats, and coverage — see liters, cans, and live fill animation.

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