Epoxy Resin Calculator
Calculate epoxy resin for a countertop, table or floor pour from area and coat depth — gallons and liters, and the kit sizes to buy.
Resin is pure volume
Epoxy has no waste factor, no bulking, no settling — the pour is a sheet of liquid of a chosen depth, so the maths is exact geometry: area times depth. One US gallon is 231 cubic inches, which at a 1/8 in flood coat covers 12.8 sq ft. This calculator works in gallons and liters and rounds your shopping up to the kit sizes resin is actually sold in — because with epoxy, running short mid-pour is not a delay, it is a ruined surface.
Gallons = area (sq ft) × depth (in) × 144 ÷ 231 · 1 gallon covers 12.8 sq ft at 1/8 in
Example: a 6 × 4 ft countertop at a standard 1/8 in coat needs 24 × 0.125 × 144 ÷ 231 = 1.87 gallons (7.08 liters) — bought as 2 × 1.5-gallon kits, or a single 3-gallon kit.
| Pour depth | Coverage per gallon | Typical use |
| 1/16 in | ≈ 25.7 sq ft | Seal coat over wood, art, photos |
| 1/8 in | ≈ 12.8 sq ft | Countertops, table tops, flood coat |
| 1/4 in | ≈ 6.4 sq ft | Bar tops, garage floors |
| 1/2 in | ≈ 3.2 sq ft | Deep pours — check the per-pour limit |
There is no waste percentage dial here on purpose — but kit rounding is your safety margin, and it is not generous: mixing cups keep a film, edges drip, and a second small batch to rescue a short pour will show a seam line under raking light. If your exact figure lands just under a kit boundary, buy the next kit size up and keep the spare sealed for repairs. Note the per-pour depth limit on your resin: table-top epoxies typically cap at 1/8–1/4 in per layer, and deep-pour products at 1/2–2 in — deeper pours go in layers, each counted by the same maths.
Frequently asked questions
How much epoxy do I need for a river table?
Figure the river channel only, not the whole table: its length × average width × depth through the slab. A 6 ft river, 8 in wide and 1.5 in deep, is 4 sq ft × 1.5 in ≈ 3.7 gallons of deep-pour resin — poured in layers within the product's limit.
Can I pour 1 inch of table-top epoxy at once?
No — standard table-top resin overheats (exotherms) past about 1/4 in: it can smoke, crack and yellow. Use a deep-pour product for thick work, or layer standard resin 1/8 in at a time, letting each layer gel first.
How do I mix part A and part B from the total?
Kits are sold by total mixed volume in the ratio on the label — most countertop epoxies are 1:1, deep-pour often 2:1. A 1.5-gallon 1:1 kit is 0.75 gal of each part. The calculator's total is the mixed figure; split it by your product's ratio.
Does temperature change how much I need?
Not the volume — the same pour needs the same resin. Temperature changes working time and cure: cold resin is thick and holds bubbles, warm resin sets fast. The coverage maths is unchanged either way.