Overview
The Paint Coverage Estimator helps you calculate how much paint you'll need for your next DIY or renovation project. Whether you're painting a single wall, a room, or an entire space, this tool simplifies the process by factoring in wall dimensions, number of coats, paint coverage efficiency, and even optional windows or doors to subtract from the area.
You can toggle between metric (meters, liters) and imperial (feet, gallons) systems. This calculator is ideal for homeowners, contractors, and anyone planning to paint efficiently without over- or underestimating the amount of paint required.
Formula & Methodology
This tool uses a straightforward formula based on the surface area and the paint's coverage efficiency:
- Total Area = (Wall Length × Wall Height) × Number of Walls – Subtracted Area
- Paint Required = Total Area × Number of Coats ÷ Coverage Rate
Paint coverage rate is usually expressed as:
- m²/liter for metric (e.g., 10 m²/liter)
- ft²/gallon for imperial (e.g., 350 ft²/gallon)
The tool adjusts units based on your selection and converts coverage values accordingly to ensure consistent results. It also optionally calculates estimated cost based on price per liter or gallon.
Example
- Unit System: Metric
- Wall Dimensions: 3 m (length) × 2.5 m (height)
- Number of Walls: 4
- Number of Coats: 2
- Coverage Rate: 10 m²/liter
- Subtracted Area: 0
Calculation:
Total Area = (3 × 2.5) × 4 = 30 m²
Paint Needed = (30 × 2) / 10 = 6 liters
You would need approximately 6 liters of paint, and the tool will suggest rounding up for purchase.
Use Cases
- Homeowners planning an interior or exterior paint job
- DIYers estimating project cost and materials
- Contractors providing quick painting quotes
- Interior designers and decorators calculating color coverage
- Real estate professionals staging properties for sale
FAQ
What is a typical paint coverage rate?
Most paints cover between 8–12 m² per liter or 300–400 ft² per gallon. Check your paint can label for accurate values.
How do I account for windows or doors?
Simply measure the area of windows or doors and enter the total in the "Subtract Window/Door Area" field to exclude it from the calculation.
What if I'm using a paint with a primer or textured finish?
These types of paint often require more volume. Reduce the coverage rate value to reflect lower efficiency.
Does this tool calculate ceiling or floor area?
This version is optimized for vertical wall surfaces. For ceilings or floors, manually enter those dimensions.