Exterior paint calculator by address
Enter an address to estimate net exterior wall area from Google's aerial roof outline and your story count. Use the typed calculator to turn wall dimensions into wall and trim gallons at your chosen coats and coverage. We haven't published a wall-area test yet; check wall heights and openings on site before ordering.
Updated
Wall area by stories
- 1 story1,574 sq ft
- 2 stories3,029 sq ft
- 3 stories4,434 sq ft
Measurements from Google aerial roof data, measured by the same engine Measured Bid prices from. No prices are shown here. Confirm every number on site.
Type the walls for paint gallons
Coats and coverage are editable starting values. Check your paint's label. Opening counts use the same area allowances as the siding calculator.
Per gallon, per coat. A starting value: check your paint's label.
1,151 sq ft × 2 coats ÷ 350 sq ft per gallon. Trim: 0 sq ft. Wall and trim gallons round up separately.
Worked out in your browser from the numbers you type. Nothing is looked up or saved. No prices are shown here. Confirm every number on site.
At a glance
| Input | What you get |
|---|---|
| Address and stories, or wall dimensions, openings, coats, coverage and trim | Net wall area by stories; typed mode adds wall gallons, trim gallons and total gallons |
| Coats, coverage and trim dimensions | Wall and trim gallons rounded separately |
How many gallons does exterior painting take?
- Multiply wall perimeter by wall height, add gable triangles and subtract windows and doors.
- Multiply net wall area by the coats you plan to apply.
- Divide by the coverage on your paint label and round up to whole gallons.
- Calculate trim separately from its length and width, using the coverage for your trim paint.
MeasuredOur model house, one story
- Net wall area from the painting model
- 1,574 sq ft
- Starting calculation: × 2 coats ÷ 350 sq ft per gallon
- 9 wall gallons
- Trim entered for this example
- 0 ft; add your measured trim
Coats and coverage are starting inputs. Use the paint label and your measured trim for an order.
How this measures
- The wall model starts with Google's aerial roof outline, subtracts the overhang, multiplies by stories and wall height, adds gable ends and deducts an allowance for openings.
- Gallons equal net area times coats divided by your coverage per gallon, rounded up. Trim paint is rounded separately.
What needs an on-site check?
- Check openings, masonry, wall heights, stepped walls and trim on site before ordering paint.
We haven't published a wall-area test yet. Address measurements use model assumptions for wall height and openings.
Measurement methods and published testsFAQ
How many gallons of paint do I need for the outside of my house?
Multiply net wall area by the number of coats, divide by your paint's coverage per gallon and round up. Calculate trim separately when it uses a different paint. The editable starting values here are two coats and 350 sq ft per gallon per coat.
How do I measure exterior wall area on my house?
Multiply the wall perimeter by wall height, add gable triangles and subtract windows and doors. Address mode estimates these quantities from the roof outline and the story count. Typed mode uses the wall dimensions and opening counts you enter.
How many coats should I enter?
Enter the coats your chosen paint and surface preparation require. Two coats is an editable starting value for this calculation. Check the product label and the condition of the existing finish.
How much paint do I need for trim?
Multiply trim length in feet by trim width in inches divided by 12 for trim square feet. Multiply by coats and divide by coverage, then round up separately from wall paint.
Is the exterior paint calculator free?
Measuring from an address needs a free Measured Bid account, with 5 measurements free and no credit card. The typed calculator needs no account.
How exact is the exterior wall area?
We haven't published a wall-area test yet. The roof outline gives a starting wall perimeter; openings and wall height use model settings. Check individual walls, openings and trim on site before ordering.
Related pages and tools
Measure your exterior walls
Type the address. Your free account measures it, and you can price it with your own rates when you're ready.