How to Calculate UV Resin for Jewelry and Charms
Stop wasting expensive UV resin. Whether you are filling open bezels, casting charms in silicone molds, or topping off cabochons, knowing the exact volume per piece lets you price accurately and order the right amount of resin for your next craft fair batch.
The Math Behind the Fill
Our calculator uses the simple volume formula: Length × Width × Depth (all in millimeters). We convert cubic millimeters to milliliters by dividing by 1,000, then to fluid ounces by dividing by 29.5735. Multiply by your cost per ounce and batch size to get total material cost.
UV Resin vs. Epoxy: Which One?
UV resin is perfect for small, thin pours (under 4 mm deep) because it cures in seconds under a UV lamp. For thicker pours or large projects, two-part epoxy is a better choice since UV light cannot penetrate deep layers. If you are working on bigger projects, try our Resin Volume Calculator for epoxy-specific measurements.
Pro Tip: Always cure UV resin in thin layers (2–3 mm at a time) to avoid tacky spots and yellowing. Multiple thin layers produce a clearer, stronger finish than one thick pour.
Ready to price your finished pieces? Use our Etsy Profit Calculator to make sure every charm covers your materials, fees, and profit margin.
Frequently Asked Questions
What is the difference between UV resin and epoxy resin?▼
UV resin cures in minutes under a UV lamp and comes pre-mixed in a single bottle, making it ideal for small jewelry pieces and charms. Epoxy resin requires mixing two parts (resin + hardener) and takes hours to cure, but it is better suited for large pours like river tables and coasters.
How much UV resin do I need per bezel?▼
It depends on your bezel dimensions. Measure the interior length, width, and depth in millimeters, then enter them above. A typical 25mm round bezel that is 3mm deep uses roughly 1.5 ml (about 0.05 oz) of UV resin per piece.
Can I use this calculator for silicone molds?▼
Yes. As long as you measure the interior cavity dimensions (length, width, and depth) in millimeters, this calculator works for any rectangular mold or bezel shape. For irregular shapes, measure the bounding box and expect to use slightly less resin than calculated.