Calculate the amount of resin needed for your epoxy projects including molds, coatings, river tables, and resin art.
Recommended: 15-25%
Accurate resin calculation is crucial for successful epoxy projects. Whether you're creating resin art, coating surfaces, filling molds, or building river tables, knowing exactly how much resin to mix prevents waste and ensures you have enough material to complete your project in one pour.
This calculator helps you determine the precise amount of resin needed based on your project dimensions, type, and coating thickness, accounting for waste and ensuring optimal results.
Resin is measured by volume (milliliters or fluid ounces) and calculated based on the space it needs to fill:
Volume = Length × Width × Height (or Depth)
For rectangular molds or coatings, multiply all three dimensions. For circular molds, use πr²h (pi × radius² × height).
Calculate the internal volume of your mold. For complex shapes, fill the mold with water and measure the water volume. Add 10-15% extra for waste and spillage.
Typical coating thickness ranges from 1/16 inch (1.5mm) for thin coats to 1/8 inch (3mm) for standard coats. Self-leveling resin naturally spreads to about 1/8 inch thickness.
Measure the river channel volume carefully. Account for irregular shapes by breaking the channel into sections. Deep pours may require multiple layers with cure time between pours.
For petri dishes, geodes, and abstract art, calculate based on canvas or panel size and desired depth. Multiple thin layers create better effects than single thick pours.
Most epoxy resins use specific mixing ratios that must be followed precisely:
Equal parts resin and hardener by volume. Easy to measure and mix. If you need 200ml total, mix 100ml resin + 100ml hardener.
Two parts resin to one part hardener. For 300ml total, mix 200ml resin + 100ml hardener.
Four parts resin to one part hardener. Common in marine and industrial epoxies. For 500ml total, mix 400ml resin + 100ml hardener.
Approximate coverage rates for different coating thicknesses:
| Coating Thickness | Coverage per Liter | Coverage per Gallon |
|---|---|---|
| 1/16 inch (1.5mm) | ~6.5 sq ft | ~25 sq ft |
| 1/8 inch (3mm) | ~3.3 sq ft | ~12.5 sq ft |
| 1/4 inch (6mm) | ~1.6 sq ft | ~6 sq ft |
| 1/2 inch (12mm) | ~0.8 sq ft | ~3 sq ft |
Always mix more resin than your calculated amount to account for:
A general rule is to add 15-20% extra to your calculated volume for most projects. For beginners or complex projects, consider adding 25-30% extra.
Calculate Cost per Volume
Divide the total kit price by the volume to get cost per milliliter or fluid ounce. This helps compare different brands and sizes.
Bulk Buying Savings
Larger kits (gallon vs. quart) typically offer better value per volume. Consider your storage capacity and shelf life (usually 1-2 years unopened).
Include Additional Materials
Factor in costs for pigments, mixing cups, stir sticks, gloves, and other supplies when budgeting your project.
Objects placed in resin displace volume. Subtract the volume of embedded items from your total calculation to avoid overflow.
Resin viscosity changes with temperature. Cold resin is thicker and may trap more bubbles. Warm resin (75-85°F) flows better but has shorter working time.
Large batches generate more heat and cure faster. For deep pours, mix smaller batches or use deep pour resin formulated for thicker applications.
Different resin types have maximum recommended pour depths:
Maximum pour depth: 1/4 to 1/2 inch per layer. Wait 4-6 hours between layers for thick projects.
Can pour 2-4 inches deep in a single pour. Ideal for river tables and thick castings. Slower cure time (24-72 hours).
Very thin layers only (1-2mm). UV light must penetrate to cure. Best for small jewelry and detail work.
Self-leveling formula for thin coats (1/8 inch). Excellent for bar tops, artwork, and tabletops. Fast cure (6-8 hours).