How It Works
This calculator works in 4 steps.
Enter the volume per replicate
Type the volume each well or tube receives.
Enter the counts
Type replicates per condition and the number of conditions.
Set the overage
Type the extra percent for dead volume and pipetting loss.
Read the batch volumes
The calculator returns batch volume, stock volume, and diluent volume per condition.
The Formula
The formula multiplies the per-replicate volume by the replicate count and the overage factor.
V_batch = V_rep × r × (1 + o)V_stock = C₂ × V_batch / C₁V_all = V_batch × N- V_rep:
- Volume per replicate
- r:
- Replicates per condition
- o:
- Overage fraction
- N:
- Number of conditions
Triplicate wells of 100 µL with 10% overage need a 330 µL batch per condition.
Conversion Table
The conversion table gives total batch volumes for 5 replicate designs.
| Per replicate | Replicates | Conditions | Overage | Total volume |
|---|---|---|---|---|
| 100 µL | 3 | 1 | 10% | 330 µL (0.33 mL) |
| 50 µL | 2 | 8 | 10% | 880 µL (0.88 mL) |
| 200 µL | 4 | 5 | 15% | 4,600 µL (4.6 mL) |
| 25 µL | 3 | 24 | 10% | 1,980 µL (1.98 mL) |
| 150 µL | 6 | 1 | 20% | 1,080 µL (1.08 mL) |
What Is the Replicate Dilution Calculator?
The Replicate Dilution Calculator is a tool that scales one dilution preparation to cover every replicate well or tube, so all replicates come from the same mixed batch. The calculator multiplies the per-replicate volume by the replicate count and adds an overage.
Preparing each replicate separately adds pipetting variation between replicates. One batch per condition, split into replicates, removes that source of variation. The calculator returns the batch stock and diluent volumes for each condition.
Common Uses
There are 5 main uses of this calculator.
ELISA duplicates
Users prepare one dilution per sample for 2 wells.
qPCR triplicates
Labs prepare template dilutions for 3 wells each.
Cell assay replicates
Researchers prepare treatment media for 4 to 6 wells.
Technical repeats
QC labs prepare one batch for repeated injections.
Master mixes
Users scale reaction mixes to the replicate count.