Surface takeoff
Paintable area, coats and raw coating volume before touch-up/waste allowance.
| Surface | Net area | Coats | Coverage | Coated area | Raw volume |
|---|
OneFreePlace · Tool #153
Plan paint by surface, coats, coverage and what you actually buy.
Build a multi-room project or enter measured areas directly. Subtract doors and windows, keep wall, ceiling and trim paint separate, add primer and touch-up allowance, then optimize real can sizes for minimum leftover or lowest entered cost.
✓ Multi-room project✓ Walls + ceilings + trim✓ Editable coverage + coats✓ Primer + touch-up✓ Can-size optimizer
Paint Calculator
rooms · custom areas · primer · packages · cost
Project builder
Measure the project your way.
RoomsGross wall area = 2 × (length + width) × height. Door/window allowances are subtracted from walls.
Door/window defaults are convenience allowances only. Replace them with your own measured opening areas for greater accuracy.
Finish paint assumptionsCoverage is per coat. Starting paint coverage is 375 ft²/gal (≈9.20 m²/L), but use the product label/data sheet whenever available.
| Surface | Coats | Coverage | Use |
|---|---|---|---|
| Walls | ft²/gal | ||
| Ceiling | ft²/gal | ||
| Trim / doors | ft²/gal | ||
| Other | ft²/gal |
PrimerPrimer coverage starts at 250 ft²/gal (≈6.14 m²/L), within the 200–300 ft²/gal range cited by Sherwin-Williams.
ft²/gal · manufacturer coverage and surface porosity can materially change actual use.
Can / pack optimizerChoose minimum leftover, or enter prices and let the calculator search for the lowest-cost package combination that still covers the required volume.
Prices are only needed for lowest-cost mode. Blank/zero-priced sizes are treated as unavailable. Entered prices are a shared package-price schedule for every product bucket; if wall, ceiling, trim or primer products have different prices, use volume optimization for the combined project or calculate those products separately.
Project result
Calculating—
finish paint required
Enter valid project dimensions and paint assumptions.
Net walls—after room openings
Ceilings—selected room ceilings / custom area
Trim + other—direct paintable surface area
Finish volume + allowance—before package rounding
Primer volume + allowance—before package rounding
Purchased volume—optimized package total
Estimate, not a product guaranteeActual coverage varies with product, color change, surface texture/porosity, application method and material left in tools. Use the coating's stated spread rate when available.
Shopping list
Package combinations are optimized independently unless “combine all finish paint” is selected.
| Product bucket | Need | Packages | Purchased | Leftover | Cost |
|---|
Coverage sensitivity
See how total finish-paint need changes if real-world spread rate is lower or higher than your entered coverage assumptions.
| Coverage factor | Finish volume | Change vs entered | Interpretation |
|---|
Formula audit
The room geometry, openings, coat multiplication, coverage division, allowance and package-rounding logic are shown explicitly.
Project diagnostics
Practical boundaries
Coverage is product-specificUse the actual coating's label/data-sheet spread rate when possible. Texture, porosity and application losses can materially change consumption.
EditableDoors/windows are allowancesCount-based opening subtraction uses your editable area per opening. Measure large or unusual openings directly for a tighter estimate.
Measure when neededPackage optimizer is mathematicalAvailable can sizes and prices differ by product and retailer. The optimizer does not claim a specific brand sells every package size entered here.
Shopping aidi
Why the calculator keeps surfaces separate.Wall, ceiling, trim and primer products can have different colors, finishes, spread rates and coat counts. Combining them by default would make the shopping list look precise while quietly assuming they are interchangeable.