Paint Coverage Calculator
Calculate paint needed for walls, ceilings, and rooms
Paint Settings
Paint Breakdown
What is Paint Coverage?
Paint coverage refers to the area that a gallon of paint can cover in a single coat. Understanding coverage rates helps you calculate exactly how much paint to buy, avoiding waste and ensuring you have enough to complete your project.
Common Use Cases
Room Painting
Calculate paint for bedrooms, living rooms, kitchens, and other interior spaces.
Exterior Painting
Estimate paint needed for house siding, trim, decks, and outdoor structures.
Interior Walls
Determine coverage for walls, ceilings, and accent features in homes and offices.
Budget Planning
Estimate paint costs for renovation projects and home improvement budgets.
Commercial Projects
Calculate paint requirements for offices, retail spaces, and commercial buildings.
Renovation Planning
Plan paint purchases for complete home makeovers and construction projects.
How to Use the Paint Calculator
Step 1: Choose Your Units
Select imperial (feet) or metric (meters) based on your measuring preference.
Step 2: Add Areas to Paint
Enter each wall, ceiling, or room you plan to paint with dimensions.
Step 3: Subtract Windows and Doors
Input the total area of windows and doors to exclude from paint calculations.
Step 4: Set Paint Properties
Choose number of coats, coverage rate, and whether you need primer.
Step 5: Add Pricing (Optional)
Enter paint and primer prices to get total cost estimates for your project.
Step 6: Review Results
See gallons needed, total costs, and individual area breakdowns.
Paint Types & Coverage Rates
Latex/Acrylic Paint
Coverage: 350-400 sq ft per gallon
Water-based paint ideal for interior walls and ceilings. Easy cleanup and low odor.
Oil-Based Paint
Coverage: 300-350 sq ft per gallon
Durable paint for trim, doors, and high-traffic areas. Longer drying time but excellent finish.
Primer
Coverage: 300-350 sq ft per gallon
Base coat that improves paint adhesion and coverage, especially on new or stained surfaces.
Ceiling Paint
Coverage: 350-400 sq ft per gallon
Flat finish paint designed specifically for ceilings with reduced splatter formula.
Exterior Paint
Coverage: 250-350 sq ft per gallon
Weather-resistant paint for siding, trim, and outdoor surfaces. Coverage varies by texture.
Specialty Paints
Coverage: 200-300 sq ft per gallon
Textured, metallic, or heavily pigmented paints that provide unique finishes and effects.
Surface Preparation Guide
New Drywall
Sand smooth, prime all surfaces, and fill nail holes. Use high-quality primer for best results.
Previously Painted Walls
Clean thoroughly, sand glossy areas lightly, and prime any stains or color changes.
Wood Surfaces
Sand with grain, wipe clean, and prime bare wood. Fill holes with wood filler first.
Metal Surfaces
Remove rust, clean with degreaser, and use metal primer before painting.
Textured Walls
Expect 20-30% more paint consumption. Use high-nap rollers for even coverage.
Stained Surfaces
Use stain-blocking primer first, then proceed with regular painting process.
Professional Painting Tips
Buy 10-15% Extra Paint
Always purchase slightly more paint than calculated for touch-ups and future repairs.
Use Quality Brushes and Rollers
Better tools provide smoother coverage and reduce the amount of paint needed.
Prime When Necessary
Proper priming reduces paint consumption and ensures better color accuracy.
Consider Surface Texture
Rough or porous surfaces require 20-30% more paint than smooth surfaces.
Mix Paint Batches
Combine multiple cans to ensure color consistency throughout your project.
Apply Thin, Even Coats
Multiple thin coats provide better coverage and appearance than fewer thick coats.
Professional Painter Secrets
The 2-Coat Rule
Always plan for 2 coats minimum. The first coat seals, the second coat provides the true color and finish.
Temperature Matters
Paint coverage decreases in extreme temperatures. Ideal conditions are 65-75°F with low humidity.
Box Your Paint
Mix multiple gallons together to prevent color variations between cans on large projects.
Back-Roll Spray Applications
After spraying, back-roll the surface for better coverage and to work paint into textured surfaces.
Wet Edge Technique
Always maintain a wet edge when painting to avoid lap marks and ensure seamless coverage.
Quality Over Quantity
Invest in premium paint - it covers better, lasts longer, and often requires fewer coats than budget options.
Common Painting Mistakes
Skipping Surface Preparation
Consequence: Poor paint adhesion, uneven coverage, and premature paint failure.
Not Using Primer
Consequence: Increased paint consumption, poor color accuracy, and reduced durability.
Buying Cheap Paint
Consequence: Poor coverage requiring extra coats, ultimately costing more money.
Applying Paint Too Thick
Consequence: Drips, runs, longer drying times, and wasted paint.
Not Accounting for Texture
Consequence: Running out of paint mid-project due to underestimating coverage needs.
Painting in Poor Conditions
Consequence: Uneven drying, poor coverage, and adhesion problems.
Paint Selection Guide
Choosing the right paint type for your project affects both coverage and final results.
Interior Walls
Use latex/acrylic paint in eggshell or satin finish for easy cleaning and good durability.
Ceilings
Flat finish ceiling paint minimizes imperfections and reduces glare from lighting.
Trim and Doors
Semi-gloss or gloss paint provides durability for high-touch surfaces and easy cleaning.
Bathrooms and Kitchens
Satin or semi-gloss paint withstands moisture and frequent cleaning better than flat finishes.
Exterior Siding
100% acrylic exterior paint provides weather resistance and color retention.
High-Traffic Areas
Choose washable finishes like eggshell or satin that can withstand regular cleaning.
Paint Coverage Myths vs Reality
Myth: Expensive paint always covers better
Reality: Coverage depends more on paint quality and formulation than price. Check coverage specifications.
Myth: One coat is enough for most jobs
Reality: Two coats are almost always necessary for proper coverage, color depth, and durability.
Myth: Dark colors require more coats
Reality: Deep colors often provide better coverage per coat than lighter colors due to higher pigment content.
Myth: All paints cover 400 sq ft per gallon
Reality: Coverage varies significantly by paint type, surface texture, and application method.
Myth: Primer is just expensive paint
Reality: Primer is specifically formulated to seal, bond, and provide uniform coverage for topcoats.
Myth: You can skip primer with paint+primer products
Reality: Paint+primer works for minor color changes but true primer is still needed for dramatic changes or problem surfaces.
Frequently Asked Questions
How much paint do I need for a 12x12 room?
A 12x12 room with 8-foot ceilings typically needs 2-3 gallons for walls and 1 gallon for ceiling, assuming 2 coats.
Should I subtract windows and doors from calculations?
Yes, subtract large windows and doors over 20 sq ft each. Small windows can be ignored as the extra paint covers waste and touch-ups.
How long does paint typically last once opened?
Properly stored latex paint lasts 2-10 years, oil-based paint lasts 2-15 years. Store in cool, dry places away from freezing.
When do I need primer?
Use primer when painting over stains, changing colors dramatically, painting new surfaces, or using light colors over dark.
Can I use ceiling paint on walls?
Yes, but ceiling paint is usually flat finish and may not be as durable as wall paint designed for cleaning and touch-ups.
How do I calculate paint for textured surfaces?
Add 20-30% extra paint for heavy texture, 10-15% for light texture. Rough surfaces absorb more paint than smooth ones.
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