Paint calculator
Room dimensions, coats, and whether you are priming. Gallons out, walls and ceiling separately, so the order is right the first trip.
Your numbers stay in this browser. Nothing is sent anywhere.
How it is figured
Wall area is the perimeter times the height, less about 20 square feet per door or window. Multiply by the coats and divide by the coverage on the can, usually 350 to 400 square feet a gallon for a smooth, previously painted wall. Round up to the quart.
Primer is one coat over everything when the color is changing a lot, the surface is bare drywall or patched, or you are going from flat to a sheen. Over the same color in good shape, two coats of the finish is enough.
Trim is by the linear foot and goes through a separate quart or gallon. A room of base, casing and a door uses about a quart per coat.
From the quantity to the bid
The calculator gives you the material count. The bid gives the customer one price and the scope in plain words, and keeps the count as your cost math. The how to bid painting jobs guide works the whole price with example numbers, and the painting proposal template is the layout. Materials at cost plus markup, labor at your rate, then the job price calculator adds them up and sets the deposit.
Questions contractors ask
How many gallons to paint a 12x12 room?
Walls, two coats, 8 foot ceiling, two openings: about 2 gallons. The ceiling, two coats: about 1 gallon. Primer if needed: 1 to 2 gallons.
How much does a gallon of paint cover?
350 to 400 square feet per coat on a smooth, sealed surface. Textured walls, bare drywall, and dark colors over light pull that down to 250 to 300.
One coat or two?
Two, nearly always. One coat shows roller marks and lap lines, and the warranty on the bid is yours, not the paint company's.
How do I price the painting job?
By the square foot or by the day, with prep as its own line. The <a href="/guides/how-to-bid-painting-jobs">painting bidding guide</a> works through a three-bedroom repaint both ways.
The other tools
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- Markup vs margin calculator. Enter a cost and a markup, see the price and the real margin. Or go the other way.
- Job price calculator. Materials, labor, markup, and the deposit to ask for. The number that goes on the bid.
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- Estimate checker. Paste the bid you are about to send. A score out of ten and the exact lines it is missing.
- Invoice generator. Your business, the customer, the lines, tax, the deposit already paid. A clean PDF invoice, no account.
When the number is right, put it on an estimate the customer signs on their phone. Type the job and see it, no account needed. 30 days free, then $29 a month.