Epoxy Calculator

Calculate how much epoxy resin you need — total volume, Part A & B split, waste, and kit count for coatings, countertops, and deep pours.

Coatings: 0.04–0.12 in (1–3 mm). Countertops: 1/8 in. Deep pours: see product datasheet.

Check your product label. Many table-top epoxies are 1:1; many structural epoxies are 2:1.

Epoxy Calculator — How Much Epoxy Do I Need?

This epoxy resin calculator estimates total volume, Part A and Part B amounts by mix ratio, waste allowance, and the number of kits to order. It works for coatings, countertops, floors, river tables, and deep pours in both imperial and metric units.

Epoxy Coverage Per Square Foot & Square Metre

ThicknessPer sq ft (gallons)Per sq ft (litres)Per m² (litres)Covers per gallon
1/32 in (0.8 mm)0.032 gal0.12 L0.8 L~31 ft²
1/16 in (1.6 mm)0.065 gal0.25 L1.6 L~15 ft²
1/8 in (3 mm)0.130 gal0.49 L3.0 L~8 ft²
3/16 in (5 mm)0.195 gal0.74 L5.0 L~5 ft²
1/4 in (6 mm)0.260 gal0.98 L6.0 L~4 ft²
1/2 in (13 mm)0.520 gal1.97 L13 L~2 ft²

Before waste. Add 5–10% for mixing losses. Values based on pure volume calculation — actual coverage may vary with surface porosity and application method.

Epoxy Thickness Guide by Project Type

Project typeTypical thicknessNotes
Seal coat (porous surfaces)0.5–1 mm (1/32–1/16 in)First coat to seal wood grain or concrete pores
Countertop flood coat2–3 mm (1/8 in)Standard clear finish on wood or concrete countertops
Floor coating1–3 mmOften 2 coats — prime + topcoat
Garage floor (self-levelling)3–6 mmThicker for durability under vehicle traffic
River table layerUp to 50 mm (2 in)Deep pour product required; multiple layers for deeper pours
Casting / mold fillVariesCalculate full mold volume using the deep pour mode above

How to Calculate Epoxy Quantity

The formula is straightforward: Volume = Area × Thickness. Add waste (5–10%), then split by your mix ratio to get Part A and Part B separately. Divide total volume by kit size to find how many kits to order, always rounding up.

For a 6×2 ft countertop at 1/8 inch: area = 12 ft², volume = 12 × 0.125 = 1.5 ft³ × 7.48 = 0.2 gal base. Add 5% waste = 0.21 gal total. At 1:1 ratio: 0.105 gal Part A + 0.105 gal Part B. Order one 1-gallon kit.

Frequently Asked Questions

Multiply your area by the thickness to get volume. A 6×2 ft countertop at 1/8 inch needs about 0.21 gallons including 5% waste. At 1:1 ratio that's roughly 0.1 gal Part A and 0.1 gal Part B — one 1-gallon kit covers it comfortably. The calculator above handles all conversions and splits automatically.
At 1/8 inch thickness: approximately 0.13 gallons per sq ft (1 gallon covers about 8 sq ft). At 1/16 inch (thin coating): 0.065 gal/ft². At 1/4 inch: 0.26 gal/ft². See the coverage table above for a full thickness reference. Always calculate from your actual dimensions for accuracy.
A simple rule: 1 mm thickness ≈ 1 litre per m². At 2 mm: 2 L/m². At 3 mm: 3 L/m². This comes directly from the volume calculation (1 m² × 0.001 m = 0.001 m³ = 1 L). Add 5–10% waste for mixing losses.
Most epoxies specify ratios by volume (e.g., 2:1 by volume). Some specify by weight — the proportions will differ from volume ratios. This calculator splits totals by volume. If your product requires mixing by weight, follow the manufacturer's weight ratio instructions exactly.
Standard epoxies limit single pours to 6–12 mm (1/4–1/2 inch) to prevent dangerous heat buildup (exotherm). Deep pour products allow up to 50 mm (2 inches) per layer. Always follow your product's datasheet. Use the deep pour mode and "max pour per layer" field in the calculator to plan how many layers you need.
Yes. Epoxy left in mixing cups, on tools, and in containers adds up quickly — especially on small batches. Use 5% waste for large single pours. Use 10% for multiple small mixes or complex projects. It's always cheaper to have slightly too much than to run short mid-project.
Yes — most countertop systems use a thin seal coat (0.5–1 mm) to seal pores, followed by a flood coat (2–3 mm) for the final finish. Calculate each coat separately or enter the combined thickness. Floors often need 2–3 coats totalling 3–5 mm.

Epoxy Project Checklist

Covers surface preparation, temperature requirements, mixing procedure, pour sequence, bubble removal, and cure time before use.

Download Checklist (PDF)

Planning reference only. See Methodology and Data Sources. View all project checklists →

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Disclaimer: Results are approximate planning estimates only. Actual coverage varies with surface porosity, preparation, temperature, and application technique. Always follow your product's technical datasheet.

See Methodology and Data Sources for details.