Epoxy Resin Calculator — Estimate Resin & Hardener Needs Instantly

Calculate the exact amount of epoxy resin and hardener for any coating project. Free online epoxy calculator with mix ratio support, unit conversion, and step-by-step breakdown.

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Epoxy Resin Calculator

Enter your project dimensions and mix ratio to estimate total epoxy resin and hardener needed.

Mix Ratio (Resin : Hardener) :
Enter dimensions and mix ratio, then click Calculate Epoxy Needed to see results.

Epoxy Resin Calculation Formula Explained

The epoxy resin formula calculates the total volume of mixed epoxy needed and splits it into resin and hardener components based on the manufacturer's mix ratio.

Total Volume = Length × Width × Thickness × Number of Coats
Resin Needed = Total Volume × (Resin Parts / (Resin Parts + Hardener Parts))
Hardener Needed = Total Volume × (Hardener Parts / (Resin Parts + Hardener Parts))

Variable Definitions

  • Length & Width — Surface dimensions of the area to be coated
  • Thickness — Desired coating depth (typically 3–6mm for tabletop pours)
  • Number of Coats — How many layers of epoxy will be applied
  • Resin Parts : Hardener Parts — The mix ratio specified by the epoxy manufacturer

Always add 5–10% extra to account for waste, edge coverage, and material left in mixing containers.

How to Calculate Epoxy Resin Needed for a Project

Estimating epoxy resin correctly prevents costly shortages and wasted material. Follow these steps:

  1. Measure the surface — Record the length and width of the area in consistent units (cm or inches).
  2. Determine coating thickness — Check the epoxy manufacturer's recommended pour depth. Tabletop pours are usually 3–6mm.
  3. Calculate surface area — Multiply length × width to get the total area.
  4. Calculate total volume — Multiply area × thickness × number of coats.
  5. Apply the mix ratio — Split the total volume into resin and hardener using the formula above.
  6. Add a waste buffer — Increase the estimate by 5–10% for safety.

For a 120cm × 60cm tabletop with a 3mm coat at a 2:1 mix ratio, you need approximately 2.16 liters total (1.44L resin + 0.72L hardener) before adding a waste buffer.

Epoxy Resin Calculator Examples

Example 1: Standard Tabletop Pour

A 4-foot × 2-foot tabletop with a 1/8-inch (3mm) coating, 2:1 mix ratio, single coat.

Area = 48in × 24in = 1,152 in²
Volume = 1,152 × 0.125 = 144 in³ ≈ 2.36 L
Resin = 2.36 × (2/3) ≈ 1.57 L
Hardener = 2.36 × (1/3) ≈ 0.79 L

Example 2: Countertop with Two Coats

A 200cm × 65cm countertop, 2mm per coat, 2 coats, 1:1 mix ratio.

Area = 200 × 65 = 13,000 cm²
Volume = 13,000 × 0.2cm × 2 = 5,200 cm³ = 5.2 L
Resin = 5.2 × (1/2) = 2.6 L
Hardener = 5.2 × (1/2) = 2.6 L

Example 3: Small Art Piece

A 30cm × 40cm canvas, 1.5mm coat, 3:1 mix ratio, single coat.

Area = 30 × 40 = 1,200 cm²
Volume = 1,200 × 0.15 = 180 cm³ = 0.18 L
Resin = 0.18 × (3/4) = 0.135 L
Hardener = 0.18 × (1/4) = 0.045 L

Real-World Epoxy Resin Applications

  • Tabletop & Countertop Coating: Creating glossy, durable surfaces on dining tables, bar tops, and kitchen counters with self-leveling epoxy.
  • River Tables: Filling gaps between live-edge wood slabs with tinted or clear deep-pour epoxy for decorative furniture.
  • Floor Coatings: Applying epoxy floor systems in garages, warehouses, and commercial spaces for chemical resistance and easy cleaning.
  • Art & Resin Casting: Creating jewelry, coasters, sculptures, and encapsulated objects using casting resin.
  • Boat Building & Repair: Using marine-grade epoxy for fiberglass layup, hull repairs, and waterproof sealing.
  • Carbon Fiber & Composite Work: Laminating carbon fiber or fiberglass layers with epoxy for high-strength, lightweight parts.
  • Electronics Encapsulation: Potting and sealing electronic components against moisture, vibration, and environmental damage.

People Also Ask

Multiply the surface area (length × width) by the desired coating thickness to get the total volume. Then split the total volume according to your mix ratio. For a 2:1 ratio, divide the total volume by 3 and multiply by 2 for resin and by 1 for hardener. Always add 5–10% extra for waste and edge coverage.
Common epoxy resin mix ratios are 1:1, 2:1, and 3:1 (resin to hardener by volume). Some specialty epoxies use 4:1 or 100:45 ratios. Always follow the manufacturer's specified ratio for your specific product. Using the wrong ratio can result in sticky spots, soft cured surfaces, or complete curing failure.
For tabletop and countertop epoxy pours, a thickness of 3mm to 6mm (1/8″ to 1/4″) is typical for self-leveling coating epoxies. Flood coats are thinner at 1–2mm. Deep pour epoxies can be applied up to 25mm (1″) or more per layer. Always check the manufacturer's maximum pour depth to avoid overheating and cracking.
River tables require significantly more epoxy than surface coatings. Calculate the volume of the river channel (length × average width × depth of the void). A typical medium river table with a 4-foot channel that is 8 inches wide and 1.5 inches deep requires approximately 3–5 gallons (11–19 liters) of epoxy. Use deep-pour epoxy specifically formulated for thick applications.
Yes, temperature significantly affects epoxy viscosity. Warmer temperatures (75–85°F / 24–29°C) make epoxy thinner, improving flow and coverage. Cold temperatures (below 65°F / 18°C) thicken epoxy, making it harder to spread and potentially requiring up to 15% more material. Always work within the manufacturer's recommended temperature range for best results.

Frequently Asked Questions

Yes. Toggle between Metric (centimeters, millimeters, liters) and Imperial (inches, feet, gallons) using the buttons above the input fields. All conversions are handled automatically for consistent results.
Using an incorrect mix ratio can cause incomplete curing, leaving a sticky or soft surface. Too much hardener can make the epoxy brittle; too little can prevent proper hardening. Always double-check the ratio on your epoxy product label before mixing.
Add 5–10% to your calculated total to account for material that remains in mixing cups, spills, edge overflow, and surface absorption. For porous surfaces like wood, lean toward 10–15% extra, as the first coat often soaks in more than expected.
Yes. Enter the total pour depth and the calculator will estimate the volume. However, deep pour epoxies often have maximum layer thickness limits (typically 1–2 inches per pour). If your total depth exceeds the manufacturer's limit, divide the project into multiple layers and calculate each layer separately.
1 US gallon equals approximately 3.785 liters. 1 liter equals approximately 0.264 US gallons. The calculator handles these conversions automatically when you switch between metric and imperial units.
Coating epoxy is designed for thin layers (1–6mm) and self-levels to a smooth finish. Casting epoxy is formulated for thick pours (up to several inches) with lower viscosity and slower cure times to prevent overheating. This calculator works for both; just ensure you use the correct thickness and mix ratio for your epoxy type.

Epoxy Resin Glossary

Epoxy Resin

A two-part thermosetting polymer consisting of resin and hardener that cures to a hard, durable plastic when mixed.

Hardener

The curing agent mixed with epoxy resin to initiate the chemical reaction that transforms the liquid into a solid.

Mix Ratio

The proportion of resin to hardener specified by the manufacturer (e.g., 2:1 means two parts resin to one part hardener by volume or weight).

Pot Life

The working time after mixing during which epoxy remains fluid enough to pour and spread before it begins to gel.

Self-Leveling

A property of coating epoxies that allows them to flow and settle into a smooth, even surface without manual spreading.

Deep Pour Epoxy

Epoxy formulated for thick applications (1″+), with slower curing and lower exothermic heat generation to prevent cracking.

Flood Coat

A thin, final layer of epoxy applied over a sealed surface to create a glossy, protective finish, typically 1–2mm thick.

Exothermic Reaction

The heat-releasing chemical reaction during epoxy curing. Thick pours generate more heat and can crack if not managed properly.

Editorial Review & Methodology

This epoxy resin calculator was built and reviewed by the NumbrWiz Editorial Team. The volume calculation formula is based on standard geometric principles, and the mix ratio splitting method reflects industry-standard epoxy mixing practices used by professional woodworkers, contractors, and resin artists.

  • Formula verification: Cross-checked against manufacturer technical data sheets from major epoxy brands and industry guides.
  • Unit conversion accuracy: All metric-to-imperial conversions use standard factors (1 inch = 2.54 cm, 1 US gallon = 3.78541 liters, 1 L = 1000 cm³).
  • Edge case testing: Tested with zero values, very large surfaces, fractional thicknesses, and non-standard mix ratios.
  • UX review: Designed for clear input labeling with real-time unit label updates and preset mix ratio buttons for common epoxies.

Transparency note: All calculations run client-side in your browser. No data is ever collected, stored, or transmitted. Results are for estimation purposes; always verify against manufacturer instructions and consider adding a waste buffer. For critical structural applications, consult a qualified professional.

Page last reviewed: May 2026 · NumbrWiz Editorial Team