Epoxy calculator

How the amount is worked out

The volume is plain geometry: length × width × depth for a rectangle, π × radius² × depth for a circle, and for a river table the river’s length × its average width × the depth, because only the gap between the slabs is filled. A US gallon is 231 cubic inches by definition, so the volume converts exactly to fluid ounces, gallons, millilitres and litres.

Resin and hardener are split by the product’s ratio by volume, as its maker prints it. Ratios differ a lot between products, so measure with the ratio on your own kit, and by volume unless your maker gives a weight ratio and you weigh. None of the makers below prints a waste allowance, so the calculator adds none unless you enter one.

Each product also has a maximum depth for one pour, and some limit how much you mix at once. TotalBoat’s sheets warn that pouring thicker than the maximum can overheat the cure. When a pour is deeper than the limit, the calculator splits it into layers, and when a layer is more than the product’s largest batch, into batches.

The products, from their own sheets

Each figure is that maker’s own, for that product only. To finish over cured epoxy, see the finish dry time chart.