How many ounces of epoxy per square foot?

At 1/16 inch: approximately 8 fl oz per sq ft. At 1/8 inch: 16 fl oz per sq ft. At a thin 1/32 inch seal coat: 4 fl oz per sq ft. Multiply by your surface area and number of coats to find total ounces.

Does epoxy coverage change on porous concrete?

Yes significantly. Normal concrete absorbs 10–20% more on the first coat. Rough or old concrete can absorb 30–50% more. Very porous surfaces may need a dedicated sealer coat first. Our floor calculator accounts for porosity with a 1.0–1.5× multiplier.

What is the coverage rate for tabletop epoxy?

A typical 1/8-inch tabletop flood coat covers approximately 8 sq ft per gallon on a sealed wood surface. A thin 1/16-inch seal coat first will help coverage: apply seal, let cure, then flood coat on top.

Epoxy Coverage Calculator — Sq Ft Per Gallon & Per Ounce

Q: How many square feet does 1 gallon of epoxy cover?

At 1/16 inch (62 mil): approximately 16 sq ft per gallon. At 1/8 inch: 8 sq ft. At 1/4 inch (self-leveling): 4 sq ft. These rates assume smooth, sealed concrete. Porous or rough surfaces absorb 15–50% more.

Coverage rate is the single most important number for floor coatings, tabletops, and any epoxy project where you're spreading a thin, even layer over a surface. Get it wrong and you either waste hundreds of dollars over-ordering, or run out before the job is done. This guide gives you exact coverage rates by thickness and surface type — and links to the calculator where you can plug in your exact area for precise results.

Enter your floor or surface area and coat thickness — get exact gallons, ounces, and kit count.

📏 Calculate Coverage Now ⟶

📏 Coverage Formula

How to Calculate Epoxy Coverage

The coverage formula works in reverse from the volume formula — you know the area and thickness, and need the volume:

Volume (cu in) = Area (sq in) × Thickness (in)
Fluid ounces = Volume (cu in) ÷ 1.805

Shortcut for floors:
Fl oz = Length (ft) × Width (ft) × 144 × Thickness (in) ÷ 1.805

Example: 20 ft × 15 ft floor at 1/8″ thick (1 coat):
20 × 15 × 144 × 0.125 ÷ 1.805 = 298 fl oz (2.3 gallons) per coat. For 2 coats: 596 fl oz (~4.7 gallons) + waste buffer.

📊 Coverage Rate Table

Square Feet Per Gallon by Coat Thickness

Reference table for smooth, sealed concrete (multiply by your porosity factor for porous surfaces):

Thickness	Mils	Sq Ft / Gallon	Fl Oz / Sq Ft	Typical Use
1/32″	31 mil	32 sq ft	4 fl oz	Seal / prime coat
1/16″	62 mil	16 sq ft	8 fl oz	Standard floor coat
3/32″	94 mil	10.7 sq ft	12 fl oz	Medium build coat
1/8″	125 mil	8 sq ft	16 fl oz	Tabletop flood coat
3/16″	188 mil	5.3 sq ft	24 fl oz	Heavy build
1/4″	250 mil	4 sq ft	32 fl oz	Self-leveling floor

🏠 Surface Porosity Adjustments

How Surface Type Affects Coverage

Porous surfaces absorb epoxy during the first coat, reducing effective coverage. Use these multipliers to adjust your calculations:

Surface Type	Porosity Multiplier	Notes
Polished / sealed concrete	1.0×	No additional absorption
Normal concrete (broom finish)	1.15×	Typical garage floor
Rough / acid-etched concrete	1.30×	Old or weathered slabs
Very porous / shot-blasted	1.50×	Industrial floors, bare concrete
Unsealed wood	1.30–1.60×	Seal wood first; epoxy soaks in deeply

These multipliers apply primarily to the first coat. Subsequent coats apply to an already-saturated surface and use approximately 1.0× porosity.

📋 Project Coverage Quick Reference

Common Project Sizes — Gallons Needed

All estimates use 1/8″ coat thickness, 2 coats, 1.15× porosity (normal concrete), and a 10% waste buffer:

Project Area	Net Volume	With 10% Buffer	Kit to Buy
100 sq ft	29.6 gal	32.5 gal	Three 11-gal kits
200 sq ft	59.2 gal	65.1 gal	Thirteen 5-gal kits
400 sq ft (garage)	118.3 gal	130 gal	Twenty-six 5-gal kits
20 sq ft (tabletop)	5.9 gal	6.5 gal	Two 5-gal kits
8 sq ft (bar top)	2.4 gal	2.6 gal	Three 1-gal kits

For precise figures with your exact area, use the Floor Coating calculator. These tables serve as ballpark estimates only.

Frequently Asked Questions

How many square feet does 1 gallon of epoxy cover?

At 1/16″ (62 mil): approximately 16 sq ft per gallon on smooth concrete. At 1/8″: 8 sq ft. At 1/4″ (self-leveling): 4 sq ft. Porous surfaces reduce coverage by 15–50% on the first coat. Use the floor calculator to account for your specific surface type.

How many ounces of epoxy do I need per square foot?

At 1/16″: 8 fl oz per sq ft. At 1/8″: 16 fl oz per sq ft. At a thin 1/32″ seal coat: 4 fl oz per sq ft. Multiply by your area in sq ft and number of coats for the total ounces needed (then add 10–15% waste buffer).

Does coverage change on porous concrete?

Yes — significantly on the first coat. Normal concrete absorbs 15% more epoxy than sealed concrete. Old, rough concrete can absorb 30–50% more. Always apply a dedicated seal coat first on porous surfaces, or your coverage calculations will be off and you'll get a patchy finish.

What is the coverage rate for a tabletop epoxy coat?

A standard 1/8″ tabletop flood coat covers approximately 8 sq ft per gallon on a sealed surface. On raw wood, first apply a thin seal coat (sand once cured), then apply the flood coat — wood absorbs 30–60% more on the first pass.