T&TTool & TallyBusiness calculators for service owners

Free estimating calculator

Interior Paint Estimator

Estimate wall paint gallons, paint cost, labor hours, total cost, and suggested price for an interior room or area.

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Tool & Tally calculators are for general business planning and estimating; they are not tax, legal, payroll, financial, or accounting advice. No guaranteed revenue, profit, leads, bookings, sales, rankings, or ROI. Use local codes, site conditions, supplier pricing, and professional judgment before quoting work.

Estimate planning check

Enter your assumptions.

Formula and assumptions

How the calculator works

Gallons = Ceiling(Wall Area × Coats / Coverage) Paint Cost = Gallons × Paint Price Labor Cost = (Prep Hours + Paint Hours) × Labor Rate Suggested Price = Total Cost / (1 - Target Margin)

Common mistakes this catches

  • Counting floor area instead of wall area.
  • Ignoring second coat and touch-up allowance.
  • Leaving prep, masking, moving furniture, and cleanup out of labor.

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