BuildTotals

Project ticket

How much paint for a 12x12 room?

For the initial 12×12 ft room with 8 ft walls, two doors, two windows, and two coats, the calculator estimates 2 whole gallons of finish paint at 350 sq ft/gal per coat. Primer quantity is separate.

Interior painting prep with roller tray, drop cloth, and blank walls

Start with your measurements

Size up your project

Example values are filled in. Replace them with your project measurements.

Walls only. Each door deducts 21 sq ft and each window 15 sq ft; compare these assumptions with your openings.

Before you order

  • Confirm paint coverage, finish and coats for the surface.
  • Ask whether primer is needed and calculate it from its own coverage.

Quantities to confirm

Paint purchase sheet

Planning quantityAmount
Interior finish paint2 coat(s) over net wall area at 350 sq ft/gal; round up to whole gallons.
2gal
Primer, if neededConfirm whether primer is required, its coat count and product coverage.
Confirmgal
What this estimate assumes
  • Walls only. Door allowance: 21 sq ft each; window allowance: 15 sq ft each. Net wall area: 312 sq ft.
  • Coverage is the entered 350 sq ft/gal/coat. Whole gallons do not specify can size. Primer need, coats and coverage are unconfirmed.
Name your project & add notes Optional

Includes your quantities, assumptions and space to record the supplier, confirmed quantity, quote and delivery. No account required.

How to check this list before buying

Check the paint quantity

The example starts with 384 sq ft of walls and deducts 72 sq ft for openings. The resulting 312 sq ft is multiplied by the coat count and divided by the entered coverage, then rounded up to whole gallons.

Confirm your actual opening sizes, paint coverage, and surface preparation. Primer remains unquantified until its need, coat count, and product coverage are known. Ceilings and trim are separate.

Adjust in the full paint calculator, then save the product, color, and quantity in a purchase PDF.