House Painting Cost Calculator

House painting cost depends on the total paintable surface area, the number of coats needed, paint quality, and labor rates. This calculator estimates the full project cost from the wall area you measure, the coats you plan, and your own paint and labor rates. It works for interior or exterior work; the labor table below covers both.

Basic Formula: Total Cost = (Paint Cost) + (Labor Cost) + (Supplies Cost)

Where:

• Paint Cost = (Total wall area / Coverage per gallon) × Coats × Price per gallon
• Labor Cost = Total wall area × Labor rate per sq ft
• Supplies Cost = tape, drop cloths, primer, brushes and rollers, typically 10 to 15% of the paint cost. This calculator uses 12%

Estimating wall area from room dimensions: Quick estimate: Perimeter × ceiling height = gross wall area. Subtract about 15% for windows and doors. A 12×12 room with 8-foot ceilings works out at 48 ft of perimeter × 8 ft = 384 sq ft gross, or roughly 325 sq ft once you take out a door and a couple of windows.

Paint coverage per gallon:

Labor cost per square foot (US averages, 2025):

Cost by room (US averages):

Factors that increase cost:

• Dark-to-light color changes (extra coats or primer needed)
• High ceilings above 8 ft, which mean scaffolding or extension poles
• Textured walls (use more paint, harder to cover evenly)
• Lead paint removal (in homes built before 1978)
• Extensive wall repair (patching holes, skim coating)

Number of coats:

• Same or similar color: 1–2 coats
• Dramatic color change: 2–3 coats (plus primer)
• New drywall: 1 primer coat + 2 finish coats

Tips to reduce cost:

• Buy paint during sales (holiday weekends often have 30–40% off).
• Do your own prep work (cleaning, taping, moving furniture) to reduce labor hours.
• Choose lighter colors that cover in fewer coats.
• Get at least 3 quotes from professional painters.