How Many Square Feet Does 1 Gallon of Paint Cover?

If you’re planning a painting project, one of the most important questions is: how many square feet cover 1 gallon of paint?

The answer depends on:

Surface texture
Paint type
Number of coats
Wall condition

However, the general rule is simple:

One gallon of paint typically covers 350 to 400 square feet with a single coat.

That estimate works for most smooth interior walls, but actual coverage can vary significantly depending on the project.

In this guide, you’ll learn exactly how paint coverage works, how to calculate your needs accurately, and how to avoid buying too much or too little paint.

Quick Answer

Standard paint coverage:

$1 \text{ gallon of paint} = 350 \text{ to } 400 \text{ square feet}$ 1 gallon of paint=350 to 400 square feet

Typical Coverage:

Smooth walls → closer to 400 sq ft
Rough or textured walls → closer to 300–350 sq ft

Standard Paint Coverage Explained

Paint manufacturers estimate coverage using:

Smooth surfaces
One coat
Proper application methods

Coverage assumes:

Minimal absorption
Even paint thickness
Standard wall texture

How Many Square Feet Cover 1 Gallon of Paint?

The most common estimate is:

$350 \text{ to } 400 \text{ sq ft per gallon}$ 350 to 400 sq ft per gallon

This means:

A medium-sized bedroom may need 1 gallon
Larger rooms often require 2+ gallons

Interior vs Exterior Paint Coverage

Interior Paint

Usually covers:

350–400 sq ft per gallon

Smooth drywall provides better coverage.

Exterior Paint

Typically covers:

250–350 sq ft per gallon

Exterior surfaces absorb more paint because of:

Texture
Weather damage
Porous materials

Factors That Affect Paint Coverage

1. Surface Texture

Rough surfaces absorb more paint.

Examples:

Brick
Stucco
Popcorn ceilings

2. Number of Coats

Two coats may double paint usage.

Formula:

$\text{Total Paint Needed} = \frac{\text{Square Footage} \times \text{Number of Coats}}{\text{Coverage Per Gallon}}$ Total Paint Needed=Coverage Per GallonSquare Footage×Number of Coats

3. Paint Quality

Higher-quality paint often:

Covers better
Requires fewer coats

4. Primer Usage

Primers reduce paint absorption.

5. Color Changes

Painting:

Dark to light
Light to dark

Usually requires extra coats.

Paint Coverage Chart by Surface Type

Surface Type	Coverage Per Gallon
Smooth drywall	400 sq ft
Textured wall	300–350 sq ft
Brick	250–300 sq ft
Stucco	200–300 sq ft
Wood siding	250–350 sq ft

How to Calculate Paint Needed

Step 1: Measure Wall Area

Example:

Room walls total = 800 sq ft

Step 2: Subtract Doors and Windows

Subtract:

10–20% for openings

Example adjusted area:

700 sq ft

Step 3: Divide by Paint Coverage

$700 \div 350 = 2 \text{ gallons}$ 700÷350=2 gallons

Step 4: Adjust for Multiple Coats

Two coats:

$2 \times 2 = 4 \text{ gallons}$ 2×2=4 gallons

Real-World Paint Examples

Example 1: Bedroom

12×12 room
Smooth walls

Usually requires:

1–2 gallons

Example 2: Exterior Wall

Rough stucco surface

Coverage may drop to:

250 sq ft per gallon

Example 3: Ceiling Paint

Ceilings often absorb more paint due to texture.

Common Paint Estimation Mistakes

Forgetting Multiple Coats

One coat is rarely enough.

Ignoring Surface Texture

Textured walls require more paint.

Not Using Primer

Increases paint consumption.

Buying Exact Amount

Always buy slightly extra.

Expert Painting Tips

Buy 10% Extra Paint

Helpful for:

Touch-ups
Future repairs

Use High-Quality Rollers

Improves paint spread efficiency.

Prime New Drywall

Prevents heavy absorption.

Mix Paint Cans Together

Ensures color consistency.

Why Paint Coverage Matters

Understanding how many square feet cover 1 gallon of paint helps you:

Budget accurately
Avoid wasted paint
Prevent shortages mid-project
Improve painting efficiency
Achieve professional-looking results

Paint Coverage Formula Summary

Standard estimate:

$1 \text{ gallon} \approx 350 \text{ to } 400 \text{ square feet}$ 1 gallon≈350 to 400 square feet

Always adjust for:

Surface type
Number of coats
Paint quality

FAQs

1. How many square feet does 1 gallon of paint cover?

Usually 350–400 square feet per coat.

2. Does textured wall reduce paint coverage?

Yes, textured surfaces absorb more paint.

3. Is exterior paint coverage lower?

Yes, exterior materials usually require more paint.

4. How many coats should I apply?

Most projects need at least two coats.

5. Should I buy extra paint?

Yes, 10–15% extra is recommended.

Conclusion

So, how many square feet cover 1 gallon of paint? In most cases, one gallon covers approximately 350 to 400 square feet with a single coat on a smooth surface.

However, real coverage depends on:

Wall texture
Paint quality
Number of coats
Surface condition

By understanding these factors, you can estimate paint needs accurately, reduce waste, and complete your painting project with confidence.