LEARN TO CALCULATE · USA

Paint guides, in plain English.

Step-by-step methods, coverage tables and buying criteria for American projects: square feet, gallons, quarts and 5-gallon pails.

ALL OUR US GUIDES

Every guide, in English.

MAIN GUIDE

How much paint do I need?

The full estimation method: area, coats, coverage and waste, with per-gallon tables for BEHR, Sherwin-Williams and KILZ.

CALCULATOR

Paint calculator

Skip the math: enter your wall area or room dimensions and get gallons, quarts and 5-gallon pails with real-world coverage.

ROOM MATH GUIDE

How much paint for a 12×12 room?

Short answer: about 2 gallons for the walls of a 12×12 room with 8 ft ceilings, two coats — and roughly half a gallon more if the ceiling is included.

PRIMER GUIDE

How much primer do I need?

Fresh drywall, stains or a big color change all start with primer. Here is the practical math: coverage per gallon, how many coats, and how much to buy.

ENAMEL GUIDE

Enamel and trim paint: how much do you need?

Doors, baseboards and cabinets take enamel. Coverage runs a bit lower than wall paint — here is the math per gallon and per room.

GARAGE FLOOR GUIDE

Epoxy floor paint: how much do I need?

Garage and workshop floors are kits, not gallons of paint. Here is how to size the kit, count coats, and avoid the classic mid-floor shortage.

EXTERIOR GUIDE

Elastomeric coating: coverage for exterior walls

For stucco, block and masonry that crack and take water, elastomerics bridge hairline fissures. Coverage is much lower than house paint — here is how to plan it.

COATS GUIDE

How many coats of paint do you need?

One coat touches up, two coats are the standard, and three rescue difficult colors. Here is how to decide — and what each option consumes in gallons.

CEILING GUIDE

How much paint do I need for a ceiling?

A ceiling is measured like a floor: length × width. It just eats a little more paint and patience. The math, the margin, and the technique to finish in one trip up the ladder.

MEASURING GUIDE

How to subtract doors and windows when measuring for paint

Subtracting openings avoids buying an extra gallon — done wrong, it leaves half a wall short. Reference sizes, when to skip the deduction, and a full example.

BUDGET GUIDE

How much does it cost to paint per square foot?

Cost per square foot has three parts: the paint a wall consumes, the labor if you don't paint it yourself, and the prep. Here is the method to build a real budget.

TILE GUIDE

How many boxes of tile do I need?

Tile is sold by the box, not the piece. Here is how to measure your floor, what each standard box covers, and the waste factor to add before you pay.

LAMINATE GUIDE

How much laminate flooring do I need?

Laminate is sold by the box, not by plank. Here is how to measure the room, what each box covers, and the cutting waste the manufacturer expects you to add.

GROUT GUIDE

How much grout do I need?

Grout is bought by the pound, and consumption depends on tile size, joint width and tile thickness. Here is the industry formula, typical figures, and how many bags to buy.

WALLPAPER GUIDE

How many rolls of wallpaper do I need?

Wallpaper is bought as full double rolls, and a shortage is close to unfixable — every dye lot is unique. Here is how to measure walls, account for the pattern repeat, and buy right the first time.

EN ESPAÑOL

Guías en español.

GUÍAS COLOMBIA

Guías para Colombia

Cálculo de pintura, sellador, esmalte, epóxica e impermeabilizante en litros, galones y cuñetes, con marcas colombianas.

GUÍAS MÉXICO

Guías para México

Cálculo de pintura para aplanado, sellador, esmalte e impermeabilizante con datos de Comex y Berel: galón de 4 L y cubeta de 19 L.