Resin Coaster Calculator
Calculate exact resin amounts for single coasters or batch production. Supports round, square, and hexagon coasters in any size. No sign-ups. Instant results.
💡 Quick answer
How many coasters in a set? The standard is 4 coasters per set; 6-coaster sets are common for
larger households or gifting.
Standard 4" coaster (100mm, 8mm thick): ~63ml per coaster, ~277ml for a set of 4
Small 3.5" coaster (90mm, 6mm thick): ~38ml per coaster, ~168ml for a set of 4
Large 4.7" coaster (120mm, 10mm thick): ~113ml per coaster, ~497ml for a set of 4
All amounts include 10% buffer. Use the calculator below for your exact mold size.
💡 Tip: Use quality silicone coaster molds and a digital scale for accuracy. Ready to pour? Shop table top epoxy resin and mica powder colorants.
🍵 Selling coasters? See our Food Safe Epoxy Guide to confirm your resin formula is safe for use with hot mugs and choose the right brand.
Example calculation
Let's calculate resin needed for a standard coaster set of 4:
| Parameter | Value |
|---|---|
| Coaster shape | Round |
| Diameter | 100mm (4 inches) |
| Thickness | 8mm |
| Quantity | 4 coasters |
| Add 10% buffer | Yes |
| Total resin needed | 276 ml (or 290 grams) |
Calculation: π × (50mm)² × 8mm × 4 coasters = 251,327 mm³ = 251ml + 10% = 276ml
Common coaster sizes & resin amounts
| Coaster Size | Thickness | Resin Per Coaster | Set of 4 |
|---|---|---|---|
| Small (90mm / 3.5") | 6mm | 38ml | 152ml (168ml with buffer) |
| Standard (100mm / 4") | 8mm | 63ml | 252ml (277ml with buffer) |
| Medium (110mm / 4.3") | 8mm | 76ml | 304ml (334ml with buffer) |
| Large (120mm / 4.7") | 10mm | 113ml | 452ml (497ml with buffer) |
| Extra Large (140mm / 5.5") | 10mm | 154ml | 616ml (678ml with buffer) |
💡 Most popular: 100mm diameter at 8mm thickness (4" standard coaster size)
Resin coaster making tips
📏 Use 8mm thickness
8mm (about 5/16") is the sweet spot - thick enough to feel quality but not wasteful. Avoid going thinner than 6mm as coasters may warp.
🎨 Color in layers
For multi-color coasters, pour first color 1/3 full, let cure 4-6 hours, then add second color. Creates defined layers without bleeding.
🔥 Use a heat gun
Pop surface bubbles with a heat gun or torch within 10 minutes of pouring for crystal clear coasters.
🛡️ Add felt pads
After demolding, add self-adhesive felt circles to protect furniture and give coasters a professional finish.
🫧 Getting bubbles in your coasters?
Coaster bubbles usually come from cold resin or fast mixing. Our Bubble Troubleshooter diagnoses the exact cause in seconds.
🛒 Shop supplies: Coaster Molds • Table Top Resin • Colorants
Coaster batch production tips
For Etsy sellers & craft businesses
If you're making coasters to sell, batch production is essential for profitability. Here's how to maximize efficiency:
Work in batches of 12-24 coasters: Mix enough resin for 3-6 sets at once. This minimizes mixing time and ensures color consistency across multiple sets. For 24 standard coasters (100mm × 8mm), you'll need approximately 1,650ml of resin — use the Resin Waste Calculator to confirm the right buffer percentage for your batch size. Use the Large Pour Calculator to plan high-volume batches.
Pour strategically: Pour all coasters of the same color first before moving to the next color. This reduces cleanup time and ensures you don't waste partially mixed resin. For layered coaster designs, use the Multi-Layer Pour Calculator to plan exact depths and resin amounts per layer. Keep a timer running — most resins have 30–45 minute working time.
Calculate material costs: Use our Resin Cost Calculator to determine your per-coaster cost including resin, pigments, molds, and finishing supplies. Factor in 10-15% waste. Price sets at 3-4× material cost for healthy profit margins.
Quality control: Inspect each coaster for bubbles, dust, or uneven surfaces before adding felt pads. Sand edges smooth with 220-400 grit sandpaper if needed. Package sets in clear boxes or wrap with tissue paper for professional presentation. For a full overview of every resin calculator on this site, see the free epoxy resin calculator hub.
For a full overview of all tools on this site, see the epoxy resin calculator hub.
Resin coaster calculator FAQs
How many coasters in a set?
The standard coaster set size is 4 coasters — enough for a typical household or couple. Sets of 6 are popular for families, entertaining, or as gifts. Etsy sellers most commonly list sets of 4, with sets of 6 as an upsell option. Avoid sets of 2 or 3 — they feel incomplete and are harder to sell. Use the calculator above to get exact resin amounts for any set size.
How much resin do I need for coasters?
A standard 4-inch round coaster needs approximately 60-80ml of resin depending on thickness. For a set of 4 coasters at 8mm thick, you'll need about 280-320ml of resin total, plus 10% extra for waste. Use this calculator to get exact amounts for your specific coaster size and quantity. Always buy slightly more than calculated to avoid running short.
What is the best thickness for resin coasters?
The ideal thickness for resin coasters is 6-10mm (about 1/4 to 3/8 inch). 8mm is the most popular thickness—thick enough to feel substantial but not so thick that it uses excessive resin. Thinner coasters (4-6mm) can warp when exposed to heat, while thicker coasters (12mm+) are heavy, expensive to make, and don't add proportional value for selling purposes.
How many coasters can I make with 500ml of resin?
With 500ml of resin, you can make approximately 6-8 standard 4-inch coasters at 8mm thickness (each coaster uses 60-80ml depending on exact size). For thinner 6mm coasters, you could make 8-10 coasters. For larger 5-inch coasters, expect 5-6 coasters from 500ml. Always account for 10% waste from mixing cups and air bubbles.
Should I make coasters in one pour or multiple layers?
For standard 8mm coasters, one pour is fine and produces crystal-clear results. For thicker coasters (12mm+) or if adding embedded items like dried flowers or gold foil, pour in 2-3 layers. First layer 1/3 full, let cure 4-6 hours until tacky, add embeddings, then pour remaining resin. This prevents items from sinking and reduces heat buildup from thick pours.
Do I need to seal the bottom of resin coasters?
Yes, add felt or cork pads to the bottom of finished coasters to protect furniture surfaces and prevent scratching. Self-adhesive felt circles (3.5-4 inch diameter) or cork sheets work best. This also gives coasters a professional, finished look essential for selling on Etsy or at craft fairs. Apply felt after sanding any rough edges smooth.
What type of resin is best for coasters?
Use table top epoxy resin designed for flat pours. These resins cure crystal clear, self-level well, and handle the 8-10mm thickness in one pour. Popular brands include Stone Coat, ArtResin, and Famowood Glaze Coat. Avoid deep pour resins (designed for 2+ inch thickness) as they cure too slowly for thin coasters.
How long do resin coasters take to cure?
Most table top resins are dry to touch in 12-18 hours and fully cured in 72 hours. You can carefully demold coasters after 24 hours but wait 72 hours before sanding edges, adding felt pads, or packaging for sale. Cure time varies with room temperature—warmer rooms (75-80°F) cure faster than cold rooms (below 70°F).
How do I price resin coasters for selling?
Calculate total material cost (resin, colorants, molds, felt pads, packaging) and multiply by 3-4× for retail price. Standard coaster sets cost $4-7 in materials and sell for $18-28 on Etsy. Higher quality, unique designs command premium prices ($25-35+ per set). Use our Resin Cost Calculator to track exact costs. Factor in your time—aim for $15-25/hour profit after materials.
How much resin do I need for a coaster?
A single standard 4-inch round coaster (100mm diameter, 8mm thick) needs approximately 63ml of resin. A small 3.5-inch coaster at 6mm thick needs 38ml. A large 4.7-inch coaster at 10mm thick needs 113ml. Always add 10% buffer for waste. Use the calculator above for exact amounts based on your specific mold dimensions.