Resin Art Volume & Ratio Calculator
Enter your mold shape and resin mix ratio to get the exact weight in grams of Part A and Part B to mix — including an overfill buffer. Supports epoxy, polyester, and UV resins. Nothing uploaded.
Mix Amounts
Learn more: Resin mixing and mold geometry
Why guessing resin volume is always wrong
A round mold that is 10cm diameter and 3cm deep holds approximately 236ml of resin - not a cup, not a third of a bottle, but 236ml. At a 1:1 mix ratio that is 118ml of Part A and 118ml of Part B. Off-ratio mixing is the single most common cause of resin that never fully cures, leaving a tacky surface that cannot be fixed.
Exact resin weights in three steps
Select your mold shape (box, cylinder, hemisphere, sphere, ring, or custom volume) and enter dimensions. Specify your resin mix ratio by weight or volume, selecting from brand presets or entering custom density. The calculator returns exact grams for Part A and Part B, total mixed volume in ml, and cost estimate.
FAQ
How much epoxy resin do I need for a mold?
Measure your mold volume (length x width x depth for a box, or π x r² x h for a cylinder). Then multiply by the resin density (typically 1.1 g/ml for epoxy) to get total weight. Split by your mix ratio - a 1:1 ratio by weight means half Part A and half Part B. The calculator does all of this automatically from your mold dimensions.
What is the mix ratio for epoxy resin?
Mix ratios vary by product. Common ratios are 1:1 by volume, 2:1 by volume, or 100:87 by weight. Always check your specific product's datasheet. Enter the ratio from your product into the calculator and it will compute the correct Part A and Part B weights.
Why do I always mix too much or too little resin?
Estimating resin volume by eye almost always produces either too much (wasted expensive resin) or too little (needing a second mix that never colour-matches perfectly). The calculator eliminates guesswork by computing the exact mixed weight and split from your mold's exact dimensions.