Paint Calculator

Coverage Guide

Smooth drywall350-400 sq ft/gal
Textured walls250-300 sq ft/gal
Brick/stucco150-250 sq ft/gal
Primer250-400 sq ft/gal

Paint Types

Flat/Matte
Best for ceilings, low traffic
Eggshell
Living rooms, bedrooms
Satin
Kitchens, bathrooms, hallways
Semi-Gloss
Trim, doors, cabinets

Painting Guide

Calculating Paint Needs

Most paint covers about 350-400 square feet per gallon on smooth surfaces. Calculate your wall area, subtract doors and windows, then divide by coverage rate.

Formula

Gallons = (Wall Area - Openings) × Coats ÷ Coverage

When to Use Primer

Primer Recommended

  • New drywall or plaster
  • Covering dark with light color
  • Stained or smoke-damaged walls
  • Previously glossy surfaces
  • Painting over wallpaper

Paint+Primer OK

  • Previously painted surfaces
  • Similar color changes
  • Good condition walls
  • Non-porous surfaces

Number of Coats

SituationCoats
Same or similar color1-2
Light over dark2-3
Dark over light2
New drywall (primed)2
Bold/bright colors (red, yellow)2-3

Paint Finishes

FinishSheenBest For
Flat/Matte0-5%Ceilings, low-traffic rooms
Eggshell10-25%Living rooms, bedrooms
Satin25-35%Kitchens, bathrooms, kids' rooms
Semi-Gloss35-70%Trim, doors, cabinets
High-Gloss70%+Furniture, accents

Painting Tips

  • Buy 10% extra for touch-ups and to keep for future repairs
  • Store paint information (color, brand) for future reference
  • Higher quality paint often covers better, needing fewer coats
  • Stir paint thoroughly before and during use
  • Use painter's tape for clean edges
  • Paint in good ventilation and proper temperature (50-85°F)

Frequently Asked Questions

How much paint do I need for a room?

Calculate wall area (perimeter x height), subtract 20 sq ft per door and 15 sq ft per window, multiply by number of coats, then divide by 350-400 sq ft (coverage per gallon). Add 10% for waste and touch-ups.

How many coats of paint do I need?

Most projects need 2 coats for even coverage. Use 1 coat for similar colors, 2-3 coats when covering dark with light colors, and always 2 coats over primer on new drywall. Quality paint often covers better in fewer coats.

Do I need primer?

Use primer for: new drywall, stained surfaces, dramatic color changes (especially dark to light), previously glossy surfaces, and covering wallpaper. Paint-and-primer combos work for minor color changes on already-painted surfaces.

What paint finish should I use?

Flat/matte for ceilings and low-traffic areas. Eggshell for living rooms and bedrooms. Satin for kitchens, bathrooms, and hallways (washable). Semi-gloss for trim, doors, and cabinets. Higher sheen = more durable but shows imperfections.