Resin Calculator
Free resin calculator: enter your project's length, width and depth to get the total mixed resin in fluid ounces, millilitres and weight, with the formula shown.
Updated 2026-06-14 · Free · No sign-up · Runs privately in your browser
Show the formula & steps
How the Resin Calculator Works
This calculator tells you exactly how much mixed resin to prepare for any flat, rectangular project — a tabletop coat, a tray, a coaster set or a shallow cast. Enter the length, width and depth (coat thickness) in inches, plus the resin density, and it returns the total volume in fluid ounces and millilitres along with the weight.
The Formula
Resin coverage is a simple volume calculation:
Volume (in³) = length × width × depth Fluid ounces = volume ÷ 1.8047 (1 US fl oz = 1.8047 in³) Millilitres = volume × 16.387 Weight (g) = millilitres × density
The result is the total mixed volume — resin plus hardener combined. You then divide it by your kit’s mix ratio (often 1:1 or 2:1 by volume) to know how much of each part to pour.
Worked Example
For a 24 in × 12 in tabletop with a 0.125 in (1/8 in) coat of epoxy (density 1.1 g/mL):
- Volume = 24 × 12 × 0.125 = 36 in³
- Fluid ounces = 36 ÷ 1.8047 = ≈ 20 fl oz
- Millilitres = 36 × 16.387 = ≈ 590 mL
- Weight = 590 × 1.1 = ≈ 649 g (1.43 lb)
Add 5–10% extra to cover the mixing cup and drips, so prepare about 22 fl oz to be safe.
Tips for Accurate Resin Pours
- Measure depth carefully. Thickness drives the volume far more than small changes in length or width.
- Layer deep pours. Most tabletop epoxies cure best in coats of 1/8 to 1/4 in; thicker single pours can overheat and yellow.
- Match the density. Epoxy is around 1.1 g/mL, but polyester and UV resins differ — use the value on your product’s data sheet for an exact weight.
| Project | Size (L × W × depth) | Volume | Mixed resin |
|---|---|---|---|
| Coaster set | 16 × 16 × 0.25 in | 64 in³ | ≈ 35 fl oz |
| Tabletop coat | 24 × 12 × 0.125 in | 36 in³ | ≈ 20 fl oz |
| Serving tray | 18 × 12 × 0.5 in | 108 in³ | ≈ 60 fl oz |
Frequently asked questions
How much resin do I need for my project?+
Multiply length × width × depth (all in inches) to get the volume in cubic inches, then divide by 1.8047 to get US fluid ounces of total mixed resin. A 24 x 12 in surface with a 1/8 in coat needs about 36 in³, or roughly 20 fl oz of mixed resin.
Does the resin calculator give resin plus hardener combined?+
Yes. The figure shown is the total mixed volume, which is the resin and hardener added together. Split it according to your kit's mix ratio, for example 1:1 by volume means equal parts of each component.
How do I convert resin volume to weight?+
Multiply the volume in millilitres by the resin density. Most epoxy resins have a density of about 1.1 g/mL, so 600 mL of mixed resin weighs roughly 660 g. Check your product's data sheet for its exact density.
How thick should a resin coat be?+
A typical clear coat is 1/8 in (about 0.125 in) per pour. Deep-pour casting resins can go much thicker, but standard tabletop epoxies should be poured in layers no deeper than 1/8 to 1/4 in to avoid overheating.
Should I mix extra resin?+
Yes, add about 5 to 10 percent extra to cover what clings to the mixing cup, stir stick and any drips or self-leveling overflow. Running short mid-pour can leave uneven, partially cured patches.