Paint Calculator

Step 1: Measure Your Room

Calculate the total wall area by measuring the length and height of each wall. For rooms with standard 8-foot ceilings, multiply the perimeter by 8.

Step 2: Account for Windows and Doors

Subtract the area of windows and doors from the total wall area:

• Windows: Small (15 sq ft), Medium (20 sq ft), Large (25 sq ft)
• Doors: Standard door is 21 sq ft

Step 3: Consider Paint Coverage

Most paint covers 350-400 sq ft per gallon. Consider:

• Number of coats needed (typically 2 coats)
• Paint quality and coverage
• Surface texture and porosity

Step 4: Calculate Total Paint Needed

The calculator will determine:

• Total wall area in square feet
• Area of windows and doors
• Net wall area to be painted
• Total paint needed in gallons

How many cans of paint for a room?

The number of paint cans needed depends on your room size and paint coverage. For a typical 12x10 room with 8-foot ceilings, you'll need approximately 1-2 gallons of paint for two coats. Our calculator provides precise measurements based on your specific room dimensions and surface type.

How many cans of paint for a room exterior?

Exterior painting requires more paint due to rougher surfaces and weather resistance needs. For exterior walls, you'll typically need 20-30% more paint than interior walls. A 12x10 room exterior might require 1.5-2.5 gallons depending on the siding material and texture.

What factors affect paint coverage?

Several factors influence how many cans of paint you'll need:

• Surface texture: Rough surfaces like stucco require more paint than smooth drywall
• Paint quality: Premium paints often provide better coverage with fewer coats
• Color changes: Darker colors or dramatic color changes may require additional coats
• Surface preparation: Properly primed surfaces use less paint
• Application method: Spraying vs. rolling can affect coverage rates

How do I calculate paint for different room types?

Different room types have varying requirements:

• Bedrooms: Usually 1-2 gallons for standard sizes
• Living rooms: Often larger, may need 2-3 gallons
• Kitchens: Consider cabinets and backsplash areas
• Bathrooms: Smaller areas but moisture-resistant paint needed
• Exterior rooms: Include siding, trim, and weather considerations