Finishes
Paint Quantity Calculator
Enter the wall and ceiling areas, how many doors get painted, the number of coats and the coverage per gallon from the can. You get whole gallons for walls, ceiling and doors, plus a total. Walls, ceiling and doors are usually different products, so each is rounded up separately.
Result
Planning estimate- Paintable area (one coat)
- 580.00 sq ft
- Paint for walls
- 3 gal
- Paint for ceiling
- 2 gal
- Paint for doors
- 1 gal
- Total gallons (whole)
- 6 gal
- Total with quarts for the remainder
- 4 gal + 1 qt
Walls + ceiling + both faces of each door.
2.34 gal exact, or 2 gal + 2 qt if you buy quarts.
1.06 gal exact, or 1 gal + 1 qt if you buy quarts.
0.25 gal exact, or 2 qt if you buy quarts.
Each surface rounded up to the next quart, for paint sold by the quart.
How it is calculated
- 1 Door area = doors x 2 faces x area of one door face.
- 2 Gallons needed for a surface = area x coats x (1 + waste % / 100) / coverage per gallon.
- 3 Walls, ceiling and doors are each rounded up to whole gallons, and the total is the sum of the three.
- 4 For the quart option, each surface is instead rounded up to the next quarter gallon (one quart) and those quarts are added and shown as gallons plus quarts.
- 5 Paintable area (one coat) = wall area + ceiling area + door area.
Assumptions to confirm
- Coverage per gallon
- The default is 350 sq ft per gallon, a figure often quoted on product labels. Real coverage depends on the product, the surface and how it is applied. Replace it with the number on the product data sheet.
- Waste allowance
- The default is 10 percent for spills, roller loss and touch-ups. This is a rule of thumb, not a standard. Raise it for rough or absorbent surfaces.
- Door face area
- The default of 20 sq ft per door face is roughly a 3 ft by 6 ft 8 in door. Each door is counted on both faces. Edges, frames and trim are not included, so add area for them if they are painted.
- Same coats on everything
- The number of coats applies to walls, ceiling and doors alike. Primer or a different coat count for one surface is not handled; run it separately.
- Wall area
- Use the net wall area from the Room Finish Areas Calculator, or your own takeoff. Enter walls without any door area already added, since doors are handled here.
This is an early planning estimate, not a quotation. Check quantities against your drawings, your specification and the manufacturer's data.
Questions about this calculator
How much does a gallon of paint cover?
Labels commonly quote about 350 sq ft per gallon for one coat, but it varies by product and surface. Use the figure on the product data sheet.
Do I need two coats?
Two coats is a common default, but it depends on the paint, the surface and the color change. Your spec may also call for a specific number of coats or a primer.
Why are walls, ceiling and doors rounded up separately?
They are often different products or sheens and are bought in separate cans. Rounding each one up gives the number of gallons you would actually buy.
Related tools
- Room Finish Areas Floor, ceiling and wall areas plus baseboard length for a rectangular room. Open
- Waste Factor Add a waste allowance to a net quantity and round up to whole packs. Open
- Area Unit Converter Convert between square feet, square yards, square meters, acres, hectares and square inches. Open
Take these numbers off the drawings
Estimateria reads the door, hardware and finish schedules out of your PDFs into a priced grid, so the quantities you check here start from the set instead of a retype.