How to use this calculator
- Enter Wall area in sq ft.
- Enter Rate in $/sq ft — or tap a preset badge to auto-fill a typical value.
- Press Calculate. The highlighted row is your order quantity; the note beneath it translates the number into real-world terms.
Formula & constants
2026 pro interior painting: $2–$4.50/sq ft of wall area including material. Two-coat repaint of a 12×12 room (~350 sq ft walls) runs $700–$1,500 with trim. Every default in the fields above is editable — when your supplier’s spec sheet lists a different density, coverage rate or price, enter that number instead. The waste and compaction allowances follow common trade practice; see our methodology page for the derivation of each formula and the standards it references.
Where this fits in the project
Coating and finish quantities are coverage-rate problems: true surface area divided by the product’s rated coverage, plus a waste allowance. Prep drives success — a coating over unprofiled or damp concrete fails regardless of quantity accuracy.
How this connects to your project
No quantity stands alone — each material in the chain depends on the ones around it. These are the planning steps that pair with the paint cost calculator:
- Paint Calculator — Estimate painting cost from gallons needed.
- Drywall Cost Calculator — Painting cost is separate from drywall installation.
- Wallpaper Calculator — Compare paint vs wallpaper installation costs.
- Siding Calculator — Interior paint vs exterior siding cost.
- Baseboard Calculator — Baseboard painting is part of trim painting cost.
- Crown Molding Calculator — Crown molding painting is part of trim cost.
Frequently asked questions
What share of painting cost is labor?
80–85% — which is why DIY saves so much on painting versus almost any other trade.
Why do painters charge more for ceilings and trim?
Cut-in and overhead work is slow; trim requires brush finish quality — both bill at premium time rates.
Last verified: — prices reflect current national averages. See our methodology.
Estimates are for planning. Material densities, coverage rates and prices vary by region and supplier — confirm final quantities before ordering, and check local code where structural or electrical work is involved.