A gallon of paint typically covers 300 to 400 square feet with one coat on a smooth surface. The exact paint coverage per gallon depends on the product, surface texture, porosity, color change, and application method. Always check the paint label for the manufacturer’s stated coverage.
If you need two coats, plan on roughly half as much project area per gallon. For example, a 350-square-foot coverage rate means one gallon can cover about 350 square feet for one coat, but only about 175 square feet when your project needs two coats.
How Many Square Feet Does a Gallon of Paint Cover?
Most interior paints cover about 350 to 400 square feet per gallon. A broader working range is around 300 to 400 square feet per gallon, while some exterior paints list coverage as low as 250 square feet per gallon.
For example, Lowe’s Paint Calculator says paint is usually applied at 350 to 400 square feet per gallon. Its calculator also notes that the coverage listed on the paint can should be used for a more accurate estimate.
PaintCare’s Buy Right guide gives a wider range of 300 to 400 square feet per gallon and suggests using 350 square feet as a rough estimate when the product coverage is unknown.
Exterior products can have a wider spread rate. For example, BEHR’s exterior paint guide states that one gallon of BEHR paint covers 250 to 400 square feet with one coat.
This difference matters because there is no universal square foot coverage of a gallon. The number on the label is based on the specific paint formula and expected application conditions.
A practical coverage range
For a quick estimate, use:
- 300 sq. ft. per gallon: conservative estimate
- 350 sq. ft. per gallon: useful middle estimate
- 400 sq. ft. per gallon: higher-end estimate for suitable surfaces
If your wall is smooth and already painted with a similar color, you may get closer to the higher end. Rough, porous, or unpainted surfaces can use more paint.
Paint Coverage by Gallon Size
Use this table as a quick starting point. It assumes a 350-square-foot-per-gallon coverage rate and one coat.
Paint amount | Approx. coverage |
1 quart | 87.5 sq. ft. |
1 gallon | 350 sq. ft. |
2 gallons | 700 sq. ft. |
3 gallons | 1,050 sq. ft. |
4 gallons | 1,400 sq. ft. |
5 gallons | 1,750 sq. ft. |
These are estimates, not guarantees. Your paint may list a different rate.
For example, current BEHR exterior products list 250 to 400 square feet per gallon, while some interior products can have different product-specific rates.
How Many Square Feet Does a Quart of Paint Cover?
A gallon contains four quarts, so you can divide the gallon coverage by four.
Using a 350-square-foot-per-gallon estimate:
350 ÷ 4 = 87.5 square feet
So, one quart covers about 87.5 square feet with one coat at a 350-square-foot-per-gallon rate.
The actual coverage in a gallon of paint can vary, so the quart coverage will vary too.
Gallon coverage | Approx. quart coverage |
300 sq. ft. | 75 sq. ft. |
350 sq. ft. | 87.5 sq. ft. |
400 sq. ft. | 100 sq. ft. |
A quart makes sense for small projects, test areas, doors, small bathrooms, trim, or touch-ups. For a full room, compare the quart price with the cost per gallon before buying several small containers.
If you want to know more about this then read this: How much does a quart of paint cover?
How Many Square Feet Does 5 Gallons of Paint Cover?
To calculate five-gallon coverage, multiply the coverage rate by five.
At 350 square feet per gallon:
350 × 5 = 1,750 square feet
So, five gallons can cover about 1,750 square feet with one coat at that estimate.
At different coverage rates, the numbers change:
- 300 sq. ft. × 5 = 1,500 sq. ft.
- 350 sq. ft. × 5 = 1,750 sq. ft.
- 400 sq. ft. × 5 = 2,000 sq. ft.
If the project needs two coats, divide those project areas by two.
For example, five gallons at 350 square feet per gallon provides about 875 square feet of two-coat project coverage.
This is why the answer to how many square feet does 5 gallons of paint cover depends on both the product’s spread rate and the number of coats.
How Much Area Does 1 Gallon Cover With 1 vs. 2 Coats?
Coverage numbers on a paint can usually describe the amount of surface one gallon can cover under the stated conditions. They do not mean one gallon will cover the same project twice.
Here is a simple way to see it:
Coverage stated on can | One coat | Two coats |
300 sq. ft./gal | 300 sq. ft. | 150 sq. ft. |
350 sq. ft./gal | 350 sq. ft. | 175 sq. ft. |
400 sq. ft./gal | 400 sq. ft. | 200 sq. ft. |
The two-coat figures are project-area estimates, not a new manufacturer’s coverage rating.
For example, suppose your walls have 700 square feet of paintable area. At 350 square feet per gallon, one coat requires:
700 ÷ 350 = 2 gallons
For two coats:
700 × 2 ÷ 350 = 4 gallons
That is why the number of coats should be decided before you buy the paint.
A dramatic color change, poor surface condition, or deep color can also increase the number of coats needed. BEHR notes that porous, rough, textured, and previously unpainted surfaces can require more paint.
How to Calculate How Much Paint You Need
Use this formula:
Paint needed (gallons) = Wall area × number of coats ÷ coverage rate per gallon
Here is a real example. Say you have a bedroom with 400 square feet of wall space, after subtracting doors and windows. You plan on two coats, and your paint covers 350 square feet per gallon.
400 × 2 = 800 total square feet to cover 800 ÷ 350 = 2.3 gallons
Round up. Buy 3 gallons, or two gallons plus a quart for the extra. This kind of coverage in a gallon of paint math takes 60 seconds once you have your wall measurements.
How to Measure Your Paintable Wall Area
Getting an accurate number here matters more than any other step.
- Measure each wall. Multiply the width by the height for every wall you plan to paint. Do this in feet, not inches.
- Add all wall areas together. This gives you your gross wall area for the room.
- Subtract doors and windows. A standard door is about 20 square feet. An average window is about 15 square feet. Subtract these from your total.
- Add ceilings if you’re painting them. Multiply ceiling length by width and add that number separately, since ceiling paint often has a different coverage rate.
What Affects How Much Paint a Gallon Covers?
The number printed on a paint can assume certain conditions. Your project may not match those conditions.
Surface texture
Smooth walls usually give more predictable coverage.
Textured walls can require more paint because the surface has more area than a flat wall. Paint must reach the low and high points of the texture.
Heavy texture can also make rolling slower and increase paint use.
Surface porosity
Porous surfaces can absorb paint.
Bare drywall, plaster, masonry, and some wood surfaces may take more product than a properly sealed painted wall.
This is one reason surface preparation matters before the first coat.
Existing paint color
A similar color is usually easier to cover.
For example, painting a light beige wall a slightly darker beige is different from painting a bright white wall dark blue.
The larger the color change, the more likely you are to need additional coats.
New paint color
Deep or intense colors can require extra coats.
BEHR advises that dramatic color changes and deep colors can increase paint needs and may make a tinted primer useful.
Paint sheen
Flat, matte, satin, semi-gloss, and gloss paints do not always behave the same during application.
The product’s stated coverage rate is more useful than assuming every sheen has identical performance.
Primer
Primer changes the calculation because it is a separate coating.
A bare or repaired surface may need primer before the finish paint. The primer’s own coverage rate should be checked instead of treating it like regular wall paint.
Application method
A roller, brush, or sprayer can produce different material use.
Your technique also matters. Excessive loading, repeated back-rolling, overspray, or leaving paint in the tray can reduce practical coverage.
Does Primer Cover the Same Square Footage as Paint?
No. Primer can have a different spread rate from finish paint.
Lowe’s paint calculator uses about 200 to 300 square feet per gallon for primer, compared with about 350 to 400 square feet per gallon for paint as its general estimating values.
Your primer label should still be the main reference.
Primer can be especially useful on:
- Bare drywall
- Bare wood
- Repaired areas
- Stained surfaces
- Major color changes
- Some porous surfaces
The goal is not to use primer everywhere. The goal is to use the right primer when the surface or paint system calls for it.
How Much Paint Do I Need for Common Project Sizes?
The following examples use 350 square feet per gallon.
Paintable area | One coat | Two coats |
250 sq. ft. | 0.72 gal. | 1.43 gal. |
500 sq. ft. | 1.43 gal. | 2.86 gal. |
750 sq. ft. | 2.14 gal. | 4.29 gal. |
1,000 sq. ft. | 2.86 gal. | 5.71 gal. |
1,500 sq. ft. | 4.29 gal. | 8.57 gal. |
2,000 sq. ft. | 5.71 gal. | 11.43 gal. |
2,500 sq. ft. | 7.14 gal. | 14.29 gal. |
3,000 sq. ft. | 8.57 gal. | 17.14 gal. |
These numbers are mathematical estimates. You still need to consider the paint label, surface, color, texture, and waste.
For a two-coat 1,000-square-foot project, for example, the calculation gives 5.71 gallons. Buying 6 gallons is more practical than buying only 5.
Is One Gallon Enough to Paint a Room?
This is the exact question the r/paint community argues about often, and the honest answer is: it depends on the room, not a fixed rule.
- Small bathroom (under 100 sq ft of wall): One gallon is usually enough for two coats.
- Small bedroom (around 300 sq ft of wall): One gallon covers one coat. You’ll need closer to two gallons for two coats.
- Standard bedroom (350 to 450 sq ft of wall): Plan on two gallons for two coats.
- Larger bedroom (500+ sq ft of wall): Budget three gallons.
- Living room (600+ sq ft of wall): Three to four gallons, depending on ceiling height and color change.
Wall dimensions and the number of coats matter far more than the room’s floor size alone. Two bedrooms with the same square footage can need different amounts of paint if one has 8 foot ceilings and the other has vaulted ceilings.
How Much Paint Do I Need for an Exterior?
Exterior painting requires a little more measuring.
Start with the home’s perimeter and wall height.
Use:
Perimeter × wall height = main wall area
Then account for:
- Gables
- Windows
- Doors
- Trim
- Gutters
- Siding
- Stucco
- Brick or masonry
- Surface texture
- Number of coats
BEHR uses the perimeter multiplied by wall height for the main body calculation. It then adds gables and accounts for doors, windows, trim, and gutters.
Exterior surfaces can also have a lower spread rate than a smooth interior wall. BEHR lists 250 to 400 square feet per gallon for several exterior products.
For a large exterior project, use the product’s exact coverage rate rather than a generic number.
How to Avoid Buying Too Much or Too Little Paint
A good paint estimate starts with the actual project, not a guess.
Before buying, check these six things:
- Check the manufacturer’s coverage.
Use the paint label as your first reference. - Calculate the actual surface area.
Measure walls instead of using floor square footage. - Count the coats.
Two coats require twice the total paint area. - Consider surface condition.
Texture, porosity, and bare surfaces can increase paint use. - Plan color changes carefully.
A major color change may require more coats or primer. - Keep some paint for touch-ups.
Store leftover paint in a sealed container and label the room and color.
Buying all the paint for a room or exterior at the same time can also help keep the color consistent. PaintCare recommends estimating the actual project area and buying the right amount to reduce waste.
What does paint coverage mean for your budget?
Coverage affects the amount of paint you buy, so it also affects your project cost.
For example, if a gallon costs $50 and covers 350 square feet, the simple material cost is about 14 cents per square foot for one coat before waste, primer, labor, and other supplies.
For a 1,000-square-foot surface needing two coats:
1,000 × 2 = 2,000 sq. ft. of total coverage
2,000 ÷ 350 = 5.71 gallons
At $50 per gallon, the estimated finish-paint cost would be about $285.50.
Your actual price can be higher or lower based on the brand, finish, color, and product line. For example, current BEHR listings show different starting prices across product lines, so coverage and price should be checked together when comparing products.
Professional Painting Can Make Coverage More Predictable
Paint quantity is only part of a successful project. Surface preparation and application also affect how evenly the paint spreads and how many coats are needed.
If you are hiring a professional instead of doing the project yourself, painting services in San Diego can help with surface measurement, prep, primer selection, color changes, and proper application.
At San Diego Custom Painting, we help homeowners plan painting projects based on the actual surface rather than a rough “one gallon per room” rule. If you are planning a project in San Diego, contact us for a professional estimate and a clear plan for the paint, preparation, and labor your project needs.
Quick Answer Recap: How Much Does a Gallon of Paint Cover
For most common estimates, plan around 300 to 400 square feet per gallon for one coat, with 350 square feet being a useful middle estimate when the product’s coverage is unknown.
Remember these numbers:
- 1 quart: about 75 to 100 sq. ft. at 300 to 400 sq. ft./gallon
- 1 gallon: about 300 to 400 sq. ft. for one coat
- 5 gallons: about 1,500 to 2,000 sq. ft. for one coat
- Two coats: cut the project area covered by the same amount of paint roughly in half
- Primer: can have a different coverage rate from finish paint
- Rough or porous surfaces: may require more paint
The best estimate comes from your paintable surface area, number of coats, and the coverage rate printed on your product label.
Final takeaway
The most reliable way to estimate paint is not to guess by room size. Measure the paintable surface, account for doors and windows, decide how many coats you need, and divide by the coverage rate on the paint label.
That approach gives you a much better estimate than simply assuming every gallon covers the same number of square feet.
Frequently Asked Questions
How many square feet does a gallon of paint cover?
A gallon commonly covers about 300 to 400 square feet with one coat. Some products have a wider or lower stated range, so check the label before buying.
How many square feet does a quart of paint cover?
A quart is one-fourth of a gallon. At 350 square feet per gallon, a quart covers about 87.5 square feet with one coat.
How many square feet does 5 gallons of paint cover?
At 350 square feet per gallon, five gallons cover about 1,750 square feet with one coat. At 300 to 400 square feet per gallon, the range is about 1,500 to 2,000 square feet.
How much paint do I need for 1,000 square feet?
At 350 square feet per gallon, 1,000 square feet needs about 2.86 gallons for one coat. Two coats require about 5.71 gallons, so six gallons is the practical whole-gallon estimate.
Does two coats of paint double the amount of paint needed?
Yes, when the same surface receives two full coats, you need roughly twice the total paint coverage. Surface condition and product performance can change the final amount.
Does textured paint require more paint?
Textured surfaces usually need more paint than smooth surfaces because they have more surface area and can hold or absorb more product.
Does primer change how much paint I need?
Yes. Primer is a separate coating and can have its own coverage rate. Lowe’s general calculator guidance uses about 200 to 300 square feet per gallon for primer.
Is 350 square feet per gallon a good estimate?
Yes, it is a useful middle estimate when you do not know the product’s coverage rate. PaintCare recommends 350 square feet as a rough estimate, while also advising readers to use the product label when available.
