How to use (3 steps)
- Pick metric or US units and choose whether the product ratio is by weight or volume.
- Enter the mix ratio and either the total amount, a known A/B amount, or densities to convert weight to volume.
- Review the calculated amounts, copy the shareable URL, and mix thoroughly.
A 4:1 sample is prefilled. Press Calculate or edit any field to update the Part A and Part B amounts.
Mix settings
Units are for display only—keep one system per calculation.
Use the ratio type printed in the technical datasheet. If only weight is given, keep "By weight".
Inputs stay in your browser and are stored in the shareable URL.
Calculation mode
Inputs
Inputs
Inputs
Results
Auto-updated when you change any field.
Keep the same units within one batch; mix in a clean cup and scrape the sides.
Planning notes and next steps
Use this guide to size a safe batch, confirm whether the ratio is by weight or volume, and move from a sample mix to a shop-floor batch without changing the resin system.
How it works
The calculator splits total mixed material into Part A and Part B, or converts a weight ratio to a volume ratio when densities are provided. It is most useful when you keep the datasheet ratio fixed and test one batch size or density assumption at a time.
When to use
Use this page before coating, laminating, or filling when you need to estimate a batch size, convert a datasheet ratio, or brief another person with the same recipe.
Common mistakes to avoid
- Switching between weight and volume ratios without checking what the datasheet specifies.
- Changing resin ratio, total batch size, and density assumptions at the same time.
- Comparing another calculator or kit label without matching Part A/B naming, densities, and reserve allowance.
- Treating displayed rounded amounts as exact lab measurements instead of practical mix targets.
Interpretation and worked example
Start with the datasheet ratio and your planned total batch. Then test one realistic alternative, such as a smaller batch for pot life or a density-based volume conversion. If the split still matches your mixing workflow and container size, the setup is probably usable. If not, re-check ratio basis, units, and density inputs before mixing material.
See also
FAQ
Should I mix by weight or by volume?
Follow the datasheet. If only a weight ratio is provided, measure by weight. Use the converter only when you must measure by volume.
How much deviation is acceptable?
Stay within the tolerance from the manufacturer—commonly within about ±2–3%. If you overshoot, remix a fresh batch instead of trying to fix a small cup.
What should I enter first?
Start with the minimum required inputs shown above the calculate button, then keep optional settings at their defaults for a first run. After you get a baseline result, change one parameter at a time so you can see exactly what caused the output to move.
How precise are the results?
The calculator keeps internal precision and rounds only for display. Small differences can still appear when another tool uses different constants, unit assumptions, or rounding rules. Match the same assumptions before comparing values.
Why can my result differ from another epoxy calculator or kit label?
Different tools may assume weight vs volume ratios, use different density values, or round each component at different steps. Check the datasheet basis first, then compare the same unit system, densities, and total batch size before judging the difference.
What is pot life and how should I plan around it?
Pot life is the amount of usable time after Part A and Part B are mixed. Exceeding it can increase viscosity, create heat, and reduce wetting quality. To avoid surprises, mix smaller batches, keep working temperature stable, and only mix what you can coat within one pot life.
Can I mix Part A and Part B from different brands?
Not unless the datasheet explicitly lists the pair as compatible. Even when the chemistry seems similar, catalyst and solvent systems can vary, causing cure delay, poor adhesion, or brittle films.
How much extra material should I prepare?
For smooth wall and deck coating, a 5–15% reserve is common; for uneven or filled substrates, 15–30% helps prevent running out on-site. Start with a pilot batch, then add a small overage to the final estimate.