How Much Paint for a Ceiling?

A ceiling is the simplest paint calculation on this site: length times width, nothing subtracted.

A 12x12 ceiling needs 1 gallon for two coats. Ceilings are the easiest surface to estimate because nothing gets subtracted — you simply multiply length by width. Ceiling paint also covers more per gallon than wall paint, typically 400 square feet instead of 350.

Dimensions
Openings & coats
Paint & pricing

Coverage figures come from typical manufacturer labels. Always round up — leftover paint is cheaper than a second trip.

Estimates only. Textured walls, high ceilings, sprayers and major colour changes can all increase the amount you need. Always buy slightly more than the calculation suggests.

Paint needed by ceiling size

Paint needed by ceiling size
Room / surface Surface Coats Paint Paint cost
Small bathroom ceiling, 5x8 40 sq ft 2 1 gal $28
Bedroom ceiling, 12x12 144 sq ft 2 1 gal $28
Living room ceiling, 16x20 320 sq ft 2 2 gal $56
Large living room ceiling, 20x24 480 sq ft 2 3 gal $84
Whole floor, 1,200 sq ft 1,200 sq ft 2 6 gal $168
Whole floor, 1,200 sq ft, one coat 1,200 sq ft 1 3 gal $84

Two coats of ceiling paint at 400 sq ft per gallon — the typical coverage of a dedicated flat ceiling paint.

How many coats does a ceiling need?

One coat is enough if the ceiling is already white and clean, and you are refreshing it. This is the most common scenario, and it halves the paint you need.

Two coats are needed if you are changing colour, covering water stains, or painting bare or patched drywall.

A ceiling that has been stained by a leak needs a stain-blocking primer first. Painting over a water stain with ordinary ceiling paint will bring it back through within weeks.

Why ceiling paint is a different product

Dedicated ceiling paint is formulated for two things: it is flat, so it hides imperfections and does not reflect glare, and it spatters less when rolled overhead.

Do not substitute wall paint on a ceiling if you can avoid it. Wall paint in a satin or eggshell finish will show every flaw in the ceiling and will flash light back into the room.

The practical warning about ceilings

Ceilings are physically the hardest surface in a house to paint, and this affects how much paint you use as much as the maths does.

Frequently asked questions

How much paint for a 12x12 ceiling?

1 gallon for two coats at 400 square feet per gallon. The ceiling is 144 square feet, so two coats is 288 square feet — comfortably inside one gallon.

Do ceilings need two coats of paint?

Often only one, if the ceiling is already white and in good condition. Two coats if you are changing colour, covering stains, or painting new drywall.

How much does ceiling paint cover?

Dedicated ceiling paint typically covers 400 square feet per gallon, more than the 350 of most wall paint, because it is flat and less pigmented.

Should I use the same paint on the ceiling as the walls?

You can, and it is a common design choice, but use a flat finish. Standard wall paint in satin or eggshell will show ceiling imperfections.