Epoxy Resin Calculator
A rectangular mould is just width × depth × height, and one cubic centimetre is one millilitre. Resin runs a little heavier than water — epoxy sits around 1.1 g/cm³ — so a 10 × 10 × 2 cm coaster mould is 200 mL and 220 g. For a round mould, square half the diameter, multiply by π, then by the depth. Either way, measure the inside.
Your numbers
Resin needed
220g
Mould volume
200mL
Formula
Resin needed = Box width × Box depth × Box height × Resin density
Mix 5–10% more than the answer. More clings to the cup and stick than you expect, and running short mid-pour leaves a visible line where the second batch met the first. Every resin also has a maximum pour depth, usually 5–10 mm: a deep mould has to be poured in layers, so divide this weight by the number of layers.
What to enter
| Input | Default | Accepted range |
|---|---|---|
| Box width (cm)The box across, measured with the lid on. | 10 | 0.1 and up |
| Box depth (cm)The box front to back. | 10 | 0.1 and up |
| Box height (cm)The box height, lid included. | 2 | 0.1 and up |
| Resin density (g/cm³)Grams per cm³ — epoxy sits near 1.1. | 1.1 | 0.8 ~ 1.6 |
Step by step
Quick reference table
Results when only Box width (cm) changes and everything else stays put.
| Box width (cm) | Resin needed (g) | Mould volume (mL) |
|---|---|---|
| 5 | 110 | 100 |
| 7.5 | 165 | 150 |
| 10 | 220 | 200 |
| 15 | 330 | 300 |
| 20 | 440 | 400 |
What each result means
| Result | At default values |
|---|---|
| Resin needed (g)Resin needed in total, parts A and B together. | 220 |
| Mould volume (mL)What the mould holds; measure it with water. | 200 |
Common mistakes
Mix 5–10% more than the answer. More clings to the cup and stick than you expect, and running short mid-pour leaves a visible line where the second batch met the first. Every resin also has a maximum pour depth, usually 5–10 mm: a deep mould has to be poured in layers, so divide this weight by the number of layers.
Glossary
- Box width
- The box across, measured with the lid on.
- Box depth
- The box front to back.
- Box height
- The box height, lid included.
- Resin density
- Grams per cm³ — epoxy sits near 1.1.
- Resin needed
- Resin needed in total, parts A and B together.
- Mould volume
- What the mould holds; measure it with water.
Frequently asked questions
Q. How is Epoxy Resin Calculator calculated?
Resin needed = Box width × Box depth × Box height × Resin density — A rectangular mould is just width × depth × height, and one cubic centimetre is one millilitre. Resin runs a little heavier than water — epoxy sits around 1.1 g/cm³ — so a 10 × 10 × 2 cm coaster mould is 200 mL and 220 g. For a round mould, square half the diameter, multiply by π, then by the depth. Either way, measure the inside.
Q. Can you walk through an example?
With Box width 10cm, Box depth 10cm, Box height 2cm, Resin density 1.1g/cm³, the answer is Resin needed 220g.
Q. What do I need to enter?
Enter Box width, Box depth, Box height, Resin density. The result recalculates as you type, and an empty box counts as zero.
Q. How much does the answer move if I change a number?
Changing only Box width (cm) moves the answer to Box width (cm) 5 → Resin needed (g) 110 and Box width (cm) 20 → Resin needed (g) 440. The table below lays out five steps.
Q. How are the numbers rounded?
Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.
Q. Anything to watch out for?
Mix 5–10% more than the answer. More clings to the cup and stick than you expect, and running short mid-pour leaves a visible line where the second batch met the first. Every resin also has a maximum pour depth, usually 5–10 mm: a deep mould has to be poured in layers, so divide this weight by the number of layers.
Related calculators
Materials differ in density and absorption. If your label states a figure, use it — the defaults here are only common values.