How much paint do I need for a 12×12 room?

A 12×12 room with 9-foot ceilings has about 288 sq ft of wall space (minus doors/windows). With 2 coats you need roughly 1.6 gallons — buy 2 gallons for safety.

How much area does 1 gallon of paint cover?

Standard interior paint covers approximately 350 sq ft per gallon for one coat on a smooth surface. Textured or porous walls may require more.

Should I include the ceiling?

Ceiling paint is usually calculated separately. Toggle 'Include ceiling paint' to add the ceiling area. Ceilings typically need only 1 coat of ceiling-specific paint.

How many coats of paint do I need?

2 coats is standard for most projects. If painting a dark colour over light (or vice versa), you may need 3 coats. A single coat works for touch-ups over the same colour.

How do I account for waste?

Add about 10% to your calculated amount for spills, roller waste, and uneven surfaces. Buying a slightly larger can is cheaper than running out mid-job.

Paint Calculator

Calculate how much paint you need for any room. Enter room dimensions, number of doors and windows, coats, and finish type. Get total area, gallons, litres, and suggested can sizes. Free, instant, no sign-up.

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