Epoxy Calculator
Enter your surface size and how thick you want the pour to get how much mixed epoxy resin you need, with a waste allowance built in.
Epoxy is measured by volume. Multiply length by width by thickness to get the volume of the pour, then convert to gallons (or litres). Buy the combined resin-plus-hardener total — that's what this figure represents.
How to calculate how much epoxy you need
Work out the volume of the pour in cubic inches, then convert. There are 231 cubic inches in a US gallon.
Volume (cubic inches) = Length × Width × Thickness
Gallons = Volume ÷ 231
Order = Gallons × 1.10 (10% waste)
Gallons = Volume ÷ 231
Order = Gallons × 1.10 (10% waste)
| Application | Typical thickness | Coverage per gallon |
|---|---|---|
| Seal coat (brushed) | very thin | ~30–40 sq ft |
| Flood / table top coat | 1/8 inch | ~12–16 sq ft |
| Deep pour (river tables) | 1/2 inch+ | ~3–4 sq ft |
Worked example
A 48 × 24 inch table top at 1/8 inch (0.125 in) thick:
| Volume = 48 × 24 × 0.125 | 144 cu in |
| Gallons = 144 ÷ 231 | ≈ 0.62 gal |
| With 10% waste | ≈ 0.7 gallons |
Inches or centimetres?
Use the toggle to switch to metric — enter the surface in centimetres and the thickness in millimetres; the result is shown in litres.
Frequently asked questions
How much epoxy do I need for a table top?
For a standard 1/8-inch flood coat, one gallon covers about 12–16 sq ft. A typical 2 ft × 4 ft top needs roughly 0.6–0.7 gallons of mixed epoxy.
Does this include resin and hardener?
Yes. The figure is the total mixed volume, which is the resin and hardener combined — the amount you actually pour.
How much extra should I mix?
Add about 10–15% for what clings to the mixing bucket, drips over edges, and seal-coat losses. This calculator includes 10%.
Related calculators
Estimates for flat pours. Deep pours, edges, and porous surfaces need more — always check your product's coverage guidance.