How It Works
This calculator works in 4 steps.
Enter the protocol limit
Type the maximum allowed solvent percent from the protocol.
Enter the final volume
Type the volume of the well, tube, or flask.
Enter the stock's solvent content
Type the solvent percent in the stock, such as 100%.
Read the maximum and the check
The calculator returns the largest stock volume, the minimum stock strength, and pass or fail for the planned volume.
The Formula
The formula multiplies the limit by the final volume and divides by the stock's solvent fraction.
V_max = (L / 100) × V_final / φ_stockX_min = φ_stock × 100 / LPass if V_planned ≤ V_max- L:
- Protocol solvent limit (%)
- V_final:
- Final volume
- φ_stock:
- Solvent fraction in the stock
- X_min:
- Minimum stock-to-final strength (×)
A 0.1% DMSO limit in 1 mL allows at most 1 µL of 100% DMSO stock. The stock must be at least 1,000× the working concentration.
Conversion Table
The conversion table shows the maximum stock volume and minimum stock strength for 6 limits and volumes.
| Solvent limit | Final volume | Stock solvent | Max stock volume | Min stock strength |
|---|---|---|---|---|
| 0.1% | 1 mL | 100% | 1 µL | 1,000× |
| 0.5% | 1 mL | 100% | 5 µL | 200× |
| 1% | 0.2 mL | 100% | 2 µL | 100× |
| 0.1% | 10 mL | 100% | 10 µL | 1,000× |
| 0.5% | 0.1 mL | 100% | 0.5 µL | 200× |
| 2% | 0.05 mL | 50% | 2 µL | 25× |
What Is the Maximum Solvent Percentage Calculator?
The Maximum Solvent Percentage Calculator is a tool that checks whether a planned addition stays within a protocol-specified solvent limit and returns the largest stock volume the limit allows. The user enters the limit; the calculator does not set limits on its own.
Protocols state solvent limits such as "DMSO ≤ 0.1%" for primary cells or "≤ 1%" for many enzyme assays. The calculator returns the maximum stock volume, the minimum stock strength that respects the limit, and a pass or fail flag for the planned addition.
Common Uses
There are 5 main uses of this calculator.
Assay design
Developers set stock strengths that respect solvent limits.
Compound library dosing
Screening teams check acoustic dispense volumes against limits.
Solubility planning
Chemists find out whether a compound's solubility supports the needed stock strength.
Protocol audits
QA teams confirm planned additions pass solvent limits.
In vivo vehicles
Toxicologists check co-solvent levels against study limits.