?

🎨 Paint Calculator

Calculate exactly how much paint you need for walls, ceilings, and trim. No more running out mid-project or wasting money on extra gallons!

Room Paint Calculator

ft
ft
ft

Paint Estimate

2
Gallons Needed
Total Wall Area
432 sq ft
Paintable Area
390 sq ft
Coverage Needed
780 sq ft
Quarts
8 quarts

?? Tip: Always buy 10% extra for touch-ups and waste.

Calculate by Individual Walls

Enter dimensions for each wall you want to paint.

Wall 1

ft
ft

Wall Paint Estimate

1
Gallons Needed
Total Wall Area
120 sq ft
With Coats
240 sq ft

Exterior Paint Calculator

ft
ft
ft
ft

Exterior Estimate

8
Gallons Needed (2 coats)
Total Wall Area
1,780 sq ft
Paintable Area
1,520 sq ft
Trim Paint
2 gallons
Primer (if needed)
4 gallons

Paint Coverage Guide

Understanding paint coverage helps you buy the right amount. Coverage varies based on paint quality, surface texture, and application method.

Surface Type Coverage per Gallon Notes
Smooth drywall 400 sq ft Best coverage, new construction
Textured drywall 300-350 sq ft Texture absorbs more paint
Bare wood 250-300 sq ft Requires primer first
Previously painted 350-400 sq ft Good coverage if well-prepped
Stucco 150-200 sq ft Very porous surface
Brick 100-150 sq ft Highly absorbent
Concrete 200-250 sq ft Use masonry paint

Standard Deductions

  • Standard door: 21 sq ft (3' × 7')
  • Standard window: 15 sq ft (3' × 5')
  • Large window: 20-25 sq ft
  • Sliding door: 42 sq ft (6' × 7')

Painting Tips & Best Practices

Choose Quality Paint

Premium paint covers better, lasts longer, and often requires fewer coats. The extra cost pays off in coverage and durability.

Prep is Everything

Clean walls, fill holes, sand rough spots, and use painter's tape. Good prep makes for a professional finish.

Check Conditions

Paint between 50-85×F with humidity under 70%. Don't paint in direct sunlight or if rain is expected.

Two Coats Minimum

Even if one coat looks good, two coats ensure durability, even coverage, and true color depth.

? Dry Time Matters

Wait 2-4 hours between latex coats, 24 hours for oil-based. Rushing causes peeling and poor adhesion.

Buy Extra

Always buy 10-15% more paint than calculated. Same batch ensures color consistency for touch-ups.

When to Use Primer

Paint Coverage & Cost Reference Guide (2026)

Paint coverage varies by surface texture, paint quality, and application method. These standards come from major paint manufacturers (Sherwin-Williams, Benjamin Moore, Behr) and represent typical conditions:

Paint Type / Quality Coverage per Gallon Price per Gallon (2026) Best Application
Budget interior latex350×400 sq ft$20×35Rentals, single use
Mid-grade interior (Behr, PPG)400×450 sq ft$35×55Most interior walls
Premium interior (SW Emerald, BM Aura)400×450 sq ft$65×901-coat coverage, durability
Exterior (acrylic latex)300×400 sq ft$40×70Siding, trim
Primer (interior)300×400 sq ft$25×45New drywall, dark colors
Ceiling paint400×450 sq ft$25×45Flat finish, spatter resistant

Coverage Reduction Factors

? Frequently Asked Questions

How many square feet does a gallon of paint cover? +
Most quality interior paints cover 350-400 square feet per gallon on smooth surfaces. Textured walls, porous surfaces, and darker colors may require more paint. Always check the manufacturer's specifications on the can.
Do I really need two coats of paint? +
Usually yes! Two coats provide better color depth, more even coverage, and longer durability. One coat might look fine initially but often shows imperfections over time. The only exceptions are paint-and-primer combos or when painting the same color over itself.
How much extra paint should I buy? +
Buy 10-15% more than calculated. This accounts for waste, touch-ups, and future repairs. Keep leftover paint stored properly (sealed, room temperature) for 5-10 years. Always note the color name and formula!
Can I paint over dark colors with light colors? +
Yes, but you'll likely need primer and/or extra coats. Use a tinted primer close to your final color, then apply 2-3 coats. Without primer, dark colors can require 4+ coats to fully cover, wasting time and money.
What's the difference between paint finishes? +
Flat/Matte: No shine, hides imperfections, but hard to clean. Good for ceilings and low-traffic rooms.
Eggshell: Slight sheen, washable, great for living rooms and bedrooms.
Satin: Medium sheen, very durable, ideal for kitchens, bathrooms, and kids' rooms.
Semi-gloss: Noticeable shine, moisture-resistant, perfect for trim, doors, and cabinets.
Gloss: High shine, extremely durable, used for trim and doors.