How do I calculate for round molds / coasters?

For a circle, you calculate Pi × Radius² × Depth. We plan to add round mold fields soon. Meanwhile, you can estimate a round mold as a square of the same diameter, but subtract roughly 20%.

How much is a seal coat?

A seal coat (brushed on to prevent bubbles from porous wood) typically requires about 1 fluid ounce per square foot of surface area.

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Epoxy Resin Volume Calculator

Estimate how much epoxy resin you need for molds, tables, or coatings. Stop wasting expensive epoxy resin.

Enter your measurements

Length(in)

Width(in)

Thickness / Depth(in)

Important: The Exothermic Reaction

When Part A (Resin) mixes with Part B (Hardener), they create an exothermic chemical reaction (it generates heat). If you use the wrong type of resin for your depth, the heat can cause the project to crack, bubble violently, or even melt your mold!

Tabletop / Coating Resin

Designed for thin coats. Cures fast.

✓ Max pour depth: ~1/8" to 1/4"
✓ Cure time: 24-48 hours
✓ Best for: Coasters, canvases, table sealing

Deep Pour Casting Resin

Generates heat very slowly over time.

✓ Max pour depth: 1" to 4" (varies by brand)
✓ Cure time: 72 hours to 7+ days
✓ Best for: River tables, deep floral blocks

What about round molds?

Our calculator currently handles square/rectangular volumes. But finding the volume of a circular mold (like a coaster or round table) is basic geometry!

Volume = π × r² × depth

Pro tip: Calculate it as a square using the diameter, then subtract roughly 21% from the final resin amount.

Diameter

Calculating Resin for Rectangular Molds

This calculator simply multiplies length, width, and thickness to get a volume in cubic inches, and then converts it to fluid ounces. This takes the guesswork out of measuring resin for canvas coatings, table tops, or rectangular molds.

1:1 by Volume vs Weight

Most tabletop and art epoxy resins are 1:1 by volume. Note that Part A (Resin) and Part B (Hardener) often have different densities. If your epoxy brand requires mixing by weight, follow their specific weight ratios.