Epoxy Calculator
Enter your floor area and the coverage rate to get the gallons of epoxy you need per coat.
What your result means
Gallons is one coat at your product's coverage rate; the two-coat figure is what most garage floors actually need, since the first coat soaks into the concrete pores and the second is the finish. Order 10 to 20% over, because epoxy has to be mixed in full batches. Surface prep is most of the job, so etch the concrete thoroughly first.
How to use this calculator
- Measure floor area in sq ft.
- Check epoxy spec sheet for coverage rate.
- Read gallons needed.
- Order 10-20% extra - epoxy must be mixed in full batches.
- Apply two coats minimum for durability.
The formula
Divide the floor area by the coverage rate per gallon and round up. Most floors need two coats, so double it for the full job.
Worked example
Say you've got a 400 sq ft garage and the epoxy covers 400 sq ft a gallon. That's 1 gallon a coat, so buy 2 for the two coats most floors need.
Epoxy coverage rates
| Use | Coverage per gallon |
|---|---|
| Garage floor | ~400 sq ft |
| Heavy-duty industrial | ~200 sq ft |
Tips & gotchas
- Two coats minimum for durability.
- The first coat thins into the concrete pores.
- The second coat is the finish layer.
- Drop decorative flakes between coats if you want them.
- Prep is 90% of success. Etch the concrete thoroughly.
Frequently asked questions
How much epoxy for a 2-car garage?
About 400 to 500 sq ft of floor, so plan 1 to 2 gallons per coat.
How many coats of epoxy?
Two minimum. Some pros do three for extra durability.
How long does a garage epoxy floor last?
5 to 15 years depending on traffic and prep quality.
Can I apply epoxy over old paint?
No. Strip the old paint first; epoxy has to bond to bare concrete.
Do I need to etch the floor first?
Yes, with muriatic acid or an industrial etcher/degreaser.
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