Paint Calculator

Professional Paint Estimation Tool

How It Works

Plan, calculate, and estimate your paint project with confidence

Paint Calculator helps homeowners, DIYers, and professionals accurately estimate paint quantity, time, and total cost for interior and exterior projects — across multiple rooms and surfaces.

Step 1: Start a new project

  • A new project starts automatically.
  • Start fresh, or load a saved project from “Load saved…” to continue later.

Step 2: Choose what you are painting

  • Interior: walls, ceilings, trim, doors
  • Exterior: exterior walls and features
  • Ceiling: ceiling-only work
  • Trim: baseboards, crown, door/window trim

Step 3: Add rooms to your project

  • Use “+ Add room” for each space.
  • Each room can have its own measurements, doors, windows, and exclusions (fireplace, built-ins, accent walls).
  • Rename rooms for clarity (e.g., Living Room, Bedroom 1).

Step 4: Select your measurement system

  • Feet / Inches or Meters / Centimeters.
  • Switching units converts all existing inputs automatically.

Step 5: Enter room measurements

  • Option A: Length, width, height (best for rectangular rooms).
  • Option B: Direct wall area (best for irregular shapes).
  • Inputs are validated; you will be alerted if values are missing.

Step 6: Add doors and windows

  • Add quantities and sizes (standard or custom).
  • Non-paintable areas are subtracted from total surface automatically.

Step 7: Choose surfaces to paint

  • Select walls, ceiling, trim, and doors. Only selected surfaces are included in calculations.

Step 8: Configure paint settings (project-wide)

  • Number of coats, paint type, and finish.
  • Surface condition (good surfaces add 10% automatically).
  • Paint coverage rate (default 400 sq ft per gallon, custom supported).
  • Include primer if needed.

Step 9: Add cost estimation (optional)

  • Set paint and primer prices per gallon.
  • Enable labor (optional) and set labor rate.
  • Add supplies: brushes/rollers, tape, drop cloths, other.
  • All costs roll into the total estimate automatically.

Step 10: Special situations (room-specific)

  • Accent wall (different calculation).
  • Wainscoting / chair rail.
  • Crown molding.
  • Fireplace or built-ins (excluded areas).

Step 11: Review your project summary

  • Real-time totals: area, time, cost.
  • Paint required by surface and cost breakdown.
  • Shopping list (gallons and quarts) and room-by-room breakdown.

Step 12: Save, download, or share

  • Save to revisit later.
  • PDF to print or share as an estimate.
  • Share to generate a shareable project link for contractors, family, or paint stores.

Pro tips for best accuracy

  • Buy 10-15% extra paint for touch-ups.
  • Prime dark colors before switching to lighter shades.
  • Two thin coats beat one thick coat.
  • Save paint labels for future reference.
  • Best conditions: 50-85°F (10-30°C), low humidity.

About Paint Calculator

Paint Calculator is a professional paint estimation tool designed to reduce waste, save money, and simplify planning for painting projects of any size. Whether you are painting a single room or an entire property, this tool helps you calculate exact quantities, costs, and time with confidence.