How to accurately calculate the amount of epoxy resin
When working with epoxy resin, it is crucial to correctly calculate the required amount of material to avoid shortages or unnecessary waste.
The calculation depends on the volume of the mold, the density of the epoxy resin and the mixing ratio of components A and B. In this guide we explain how to accurately determine the volume in liters and the weight in kilograms for any epoxy system – and you can work it all out right here in our calculator.
01Calculating the amount by volume (in liters)
The simplest method is determining the volume of the mold. This calculation applies when the epoxy resin is measured by volume – in liters.
Volume (liters) = length (m) × width (m) × height (m)
Example: if you are casting a tabletop measuring 100 × 50 × 2 cm, first convert the units to meters:
Volume = 1.0 × 0.5 × 0.02 = 0.01 m³. Since 1 m³ = 1000 liters, the resin volume = 0.01 × 1000 = 10 liters.
When calculating in liters we use a density of 1.0 kg/l, so 10 liters ≈ 10 kg of resin.
02Calculating the amount by weight (in kg)
If the epoxy resin is mixed by weight, you must consider the density of the material, which typically ranges from 1.05 to 1.15 kg/l depending on the specific product.
Weight (kg) = volume (liters) × density (kg/l)
Example for 10 liters of resin:
- density 1.07 kg/l (e.g. LuminaCast) → 10 × 1.07 = 10.7 kg
- density 1.05 kg/l (e.g. EpoxyPlast 3D) → 10 × 1.05 = 10.5 kg
03Calculator: work out your amount
Enter the mold dimensions and the system density – the calculator instantly works out the volume in liters, the weight in kilograms (including reserve) and the split into components A and B. Everything recalculates immediately, with no form to submit.
How much resin will you need?
Split into components A and B
04Calculating components A and B by mixing ratio
Most epoxy resins are mixed at a 2:1 or 3:1 ratio (by weight or volume). For a weight-based ratio, use the following formula:
Component A = total weight × (ratio A / (A + B))
Component B = total weight × (ratio B / (A + B))
Example for a 2:1 ratio (by weight):
- total epoxy weight = 10.7 kg (LuminaCast, density 1.07 kg/l)
- Component A = 10.7 × (2 / 3) = 7.13 kg
- Component B = 10.7 × (1 / 3) = 3.57 kg
If the mixing ratio is 3:1, the calculation is the same – just adjust the values for components A and B.
05Example calculations for real projects
For guidance, here are three typical projects (volume × density 1.07 kg/l, plus a recommended +15 % reserve):
| Project | Dimensions | Volume | Weight (≈) | With +15 % reserve |
|---|---|---|---|---|
| Coaster | 10 × 10 × 1 cm | 0.1 l | 0.11 kg | 0.13 kg |
| Tabletop | 120 × 60 × 3 cm | 21.6 l | 23.1 kg | 26.6 kg |
| River table | 160 × 15 × 4 cm | 9.6 l | 10.3 kg | 11.8 kg |
For deep rivers and large castings use low-viscosity LuminaCast 9 Ocean Flow (layer up to 10 cm); for thin surface layers use table top systems.
06Density by epoxy system (approximate)
| System | Density | Note |
|---|---|---|
| LuminaCast | ≈ 1.07 kg/l | mixing ratio 2:1 by weight |
| Epoxyplast 3D | ≈ 1.05 kg/l | — |
| Other systems | 1.05–1.15 kg/l | always verify the exact value and ratio in the technical data sheet (TDS) |
- Volume in liters – volume = length × width × height (at a density of 1.0 kg/l)
- Weight in kilograms – volume × density (1.05–1.15 kg/l depending on the product)
- Components A and B – based on the mixing ratio (e.g. 2:1, 3:1)
- Recommended reserve – always +10–15 % to make sure you have enough material
Choose your epoxy resin
Turn your calculated amount into a project – casting and surface systems, pigments and accessories all in one place.
Browse epoxy resinsRelated categories and products
- Resins: casting epoxy resin, LuminaCast system, Epoxyplast 3D
- By project: resin for tables, for coasters, table top surface
- Coloring: pigments and colors
Frequently asked questions about epoxy resin quantity
How do I calculate the volume of a mold for epoxy casting?
Use the formula volume (liters) = length × width × height (in meters). Example: a mold measuring 100 × 50 × 2 cm = 1.0 × 0.5 × 0.02 = 0.01 m³ = 10 liters of epoxy resin.
How do I convert epoxy volume (liters) to weight (kg)?
Multiply the volume by the resin's density: weight = volume × density. Example: 10 liters of epoxy with a density of 1.07 kg/l = 10.7 kg. Always check the exact density in the product's technical data sheet.
How do I calculate the exact amounts of Part A and Part B based on the mixing ratio?
Use the formulas Part A = total weight × (ratio A / (A+B)) and Part B = total weight × (ratio B / (A+B)). Example: mixing ratio 2:1 and total weight 10.7 kg → Part A = 7.13 kg, Part B = 3.57 kg.
How much extra epoxy resin should I add as a safety margin?
We recommend adding 10–15 % extra material to cover uneven surfaces, small leaks or additional layers. For complex or large projects, this reserve is essential.
Is there an online epoxy resin calculator available?
Yes – you'll find the calculator right in this article (see the Calculator section). It works out the total amount in liters or kilograms and the exact quantities of Part A and Part B based on the mixing ratio.