Paint Calculator

What Paint is for

Paint Calculator is the page to open when you need paint from measurements you already have. It belongs with the other construction calculators because that is the work this arithmetic supports. The wall area this finish covers is the area in square feet. Type the entries first. The result stays hidden until you press Calculate, so a half-finished form never flashes a number you might mistake for the answer.

How to fill in this calculator

1. Width. Enter the value this part of the job needs. The unit list on this field includes in, ft, yd, cm, m.
2. Height. Enter the value this part of the job needs. The unit list on this field includes in, ft, yd, cm, m.
3. Width. Enter the value this part of the job needs. The unit list on this field includes in, ft, yd, cm, m.
4. Height. Enter the value this part of the job needs. The unit list on this field includes in, ft, yd, cm, m.
5. Width. Enter the value this part of the job needs. The unit list on this field includes in, ft, yd, cm, m.
6. Height. Enter the value this part of the job needs. The unit list on this field includes in, ft, yd, cm, m.
7. Width. Enter the value this part of the job needs. The unit list on this field includes in, ft, yd, cm, m.
8. Height. Enter the value this part of the job needs. The unit list on this field includes in, ft, yd, cm, m.
9. Width. Enter the value this part of the job needs. The unit list on this field includes in, ft, yd, cm, m.
10. Height. Enter the value this part of the job needs. The unit list on this field includes in, ft, yd, cm, m.
11. Width. Enter the value this part of the job needs. The unit list on this field includes in, ft, yd, cm, m.
12. Height. Enter the value this part of the job needs. The unit list on this field includes in, ft, yd, cm, m.
13. Width. Enter the value this part of the job needs. The unit list on this field includes in, ft, yd, cm, m.
14. Height. Enter the value this part of the job needs. The unit list on this field includes in, ft, yd, cm, m.

The form continues past those fields, 62 inputs in all. Extra rows are for a second area, a second board, or another piece of the same kind. Leave a row blank when you do not have that piece. Use Add another only when you do.

The formula in plain language

Paintable area is the wall width times the wall height for each wall, plus ceiling length times ceiling width, minus about 21 square feet for each door and 15 square feet for each window. One gallon covers about 350 square feet. Two coats double the gallons.

A worked example

A 12 by 15 foot room with 8 foot walls has 432 square feet of wall. Two doors and three windows remove about 87 square feet, leaving 345. That is just under one gallon for one coat, and just under two gallons for two coats.

Paint, drywall, and wallpaper share the wall they cover. This paint result should match drywall for the wall and wallpaper calculator.

Mistakes that move the answer

• Textured walls and bare drywall drink more paint than a previously painted smooth wall.
• The ceiling is a separate area. Leaving it out is the usual reason a job runs short.

How to check the result

After Calculate shows the paint result, redo the last operation with a pencil using the rounded figures on the screen. Matching that check means the inputs were read correctly. If you edit a label or a sentence in this HTML file, reload the page. The form and this article both live in the file, so the edit is what visitors will read.