Quick answer: Gallons from wall length, height, doors, windows and coats — plus what the paint costs. 120 ft of walls at two coats needs 5 gallons, $250–350 mid-grade.
Add up your wall lengths, set the ceiling height, subtract the doors and windows, pick your coats — the calculator turns it into gallons at honest coverage (about 375 sq ft per gallon per coat) and prices the paint by grade. The default 120 feet of wall at 8 feet with two coats needs 5 gallons: $250–350 in mid-range paint. Two coats is the honest default for any colour change, and the flag explains why bargain paint that needs three was never a bargain.
About 350–400 square feet per coat, properly loaded, on smooth sealed walls — this calculator uses 375. Fresh drywall, stucco, texture and dramatic colour changes absorb more, which is why pros quote surfaces after seeing them and why the second coat exists.
For any colour change, yes — one coat of even premium paint rarely hides fully, and touch-ups flash against single-coat walls. Same-colour refreshes can get away with one. Going dark-to-light is the three-coat case, or one tinted primer plus two.
Usually, and not for the marketing: better hide can genuinely save a coat, better scrub resistance survives cleaning, and application is smoother. At 5 gallons the gap between budget ($175–225) and premium ($400–500) is real money though — mid-range earns its position as the default.
Every calculator runs from one config: your name, your colours, your prices. Brand it below, open any tool from the catalogue, and finish a quote — the lead lands in the table here the moment the estimate unlocks. On your own site the widget works exactly like this.
| Captured | Name | Contact | Tool | Job value |
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| No leads yet — run any tool in the catalogue and finish the quote. | ||||
| Tenants signed | Avg. rent | Monthly | Annual |
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