Epoxy Calculator
Work out how much epoxy resin to mix for a tabletop, mold or round pour: total volume in fl oz, gallons, liters and ml, split into part A and part B by volume.
Interactive calculator · Method EPOXY-RESIN-1.0 · Last reviewed: 2026-11-04
Calculate your scenario
Volume = surface area × pour depth (rectangle area = length × width; round area = π × diameter² ÷ 4), plus the extra %.
Your inputs
Default worked example. Edit the inputs to calculate your scenario.
Default worked example
288 sq in × 0.125 = 36 cu in × (1 + 10%) = 649 ml, split 1:1 by volume.
How to use the calculator
Choose the shape and unit, enter the dimensions and the pour depth, add an allowance for waste, then enter the manufacturer’s mix ratio by volume.
What the result means
A 24 × 12 in surface poured 1/8 in deep with 10% extra needs about 21.94 fl oz (649 ml) of mixed epoxy, or about 10.97 fl oz each of resin and hardener at 1:1.
Formula and units
Volume = surface area × pour depth (rectangle area = length × width; round area = π × diameter² ÷ 4), plus the extra %. Cubic inches × 16.387064 = ml; cubic centimeters = ml. US fl oz = ml ÷ 29.5735; US gallons = ml ÷ 3,785.41. Part A = total × A ÷ (A + B); part B is the rest.
Worked examples
24 × 12 in tabletop, 1/8 in flood coat, 1:1: Length (rectangle): 24 in or cm; Width (rectangle): 12 in or cm; Diameter (round): 12 in or cm; Surface area (entered-area mode): 288 sq in or cm²; Pour depth (1/8 in = 0.125): 0.125 in or cm; Extra for drips, cup residue and edges: 10 %; Mix ratio part A (resin), by volume: 1 parts; Mix ratio part B (hardener), by volume: 1 parts; Shape: rect; Length unit: in.
Example result: Total mixed epoxy: 21.94 fl oz; Total in US gallons: 0.171 gal; Total in liters: 0.649 L; Total in milliliters: 649 ml; Part A (resin) by volume: 10.97 fl oz (324 ml); Part B (hardener) by volume: 10.97 fl oz (324 ml).
60 cm round pour 2 cm deep, 2:1: Length (rectangle): 24 in or cm; Width (rectangle): 12 in or cm; Diameter (round): 60 in or cm; Surface area (entered-area mode): 288 sq in or cm²; Pour depth (1/8 in = 0.125): 2 in or cm; Extra for drips, cup residue and edges: 5 %; Mix ratio part A (resin), by volume: 2 parts; Mix ratio part B (hardener), by volume: 1 parts; Shape: round; Length unit: cm.
Example result: Total mixed epoxy: 200.77 fl oz; Total in US gallons: 1.569 gal; Total in liters: 5.938 L; Total in milliliters: 5,938 ml; Part A (resin) by volume: 133.85 fl oz (3,958 ml); Part B (hardener) by volume: 66.92 fl oz (1,979 ml).
Limitations and common mistakes
The A:B split is by volume. If your product’s ratio is by weight, convert using each part’s density from the manufacturer’s data sheet, or weigh the parts per its instructions. This gives quantity only; follow the product’s own maximum pour depth, cure time and safety directions. Seal coats, edge flow and wood absorption can use more than the flat-volume estimate.
Splitting a weight-ratio product (for example 100:45 by weight) as if the numbers were volumes, which gives the wrong hardener amount.
Sources and assumptions
Method EPOXY-RESIN-1.0; last formula review 2026-11-04. Sources and their supported claims. Calculation methodology.