Paint Calculator

Calculate the exact amount of paint needed for walls, ceilings, and trim.

Paint Calculator

Enter your room dimensions and paint specifications to calculate gallons needed.

Room Dimensions

Wall Details

Doors & Windows

Standard door: 3ft × 7ft (21 sq ft)
Standard window: 3ft × 4ft (12 sq ft)

Paint Specifications

Trim & Additional Areas

Linear feet of trim, baseboards, or molding
Any additional areas like built-ins, cabinets, etc.

Waste & Safety Margin

Extra paint for touch-ups, spillage, and future repairs

How to Use the Paint Calculator

  1. Measure Your Room

    Measure the length, width, and height of your room using a tape measure. Record measurements in feet or meters.

  2. Count Doors & Windows

    Count the number of standard doors (3ft × 7ft) and windows (3ft × 4ft) to subtract from wall area.

  3. Select Paint Type

    Choose your paint type (latex, oil-based, primer) which determines coverage per gallon.

  4. Specify Coats & Trim

    Select number of coats and enter trim measurements for accurate calculations.

  5. Add Waste Factor

    Include a waste factor (typically 10-15%) for touch-ups and spillage.

  6. Calculate

    Click "Calculate Paint Needs" to get your results in gallons, quarts, and cost estimate.

Paint Coverage Guidelines

Paint Type Coverage (sq ft per gallon) Notes
Latex/Water-based 350-400 Most common for interior walls
Oil-based 300-350 Better durability, longer drying
Primer 250-300 Higher absorption on raw surfaces
High-build/Textured 200-250 Thicker application for texture
Exterior Paint 250-350 Varies by surface texture

Tips for Accurate Paint Estimates

Common Painting Projects & Estimates

Standard Bedroom

12' × 14' × 8' room with 1 door, 2 windows

  • Walls & ceiling: 2.5-3 gallons
  • 2 coats, latex paint
  • Trim: 0.5 gallon

Average Kitchen

10' × 12' × 8' room with cabinets

  • Walls only: 1.5-2 gallons
  • Cabinets: 1-1.5 gallons
  • Primer included

Living Room

15' × 20' × 9' room with large windows

  • Walls & ceiling: 3.5-4 gallons
  • High ceilings require more
  • Accent wall: +0.5 gallon