Volume Percent Calculator (v/v)

Pick a mode, enter volumes with units, and submit. The input grid is 3 columns on large screens, 2 on medium, and 1 on small.

Example data table

These examples assume ideal mixing and are intended for quick checks.

Formula used

Volume percent (v/v%) expresses the fraction of solute volume within the total solution volume:

• V_solute is the solute volume.
• V_total is the final solution volume.
• For reverse calculations: V_solute = (v/v% ÷ 100) × V_total.

How to use this calculator

1. Select a calculation mode (direct percent or reverse planning).
2. Enter required volumes and choose units (µL, mL, or L).
3. Set display precision for percent and volumes.
4. Press Calculate to show results above the form.
5. Use Download CSV or Download PDF in the result card for records.

Why v/v% matters in routine formulation

Volume percent is commonly used for liquid–liquid mixtures where volumes are directly measured with cylinders or pipettes. It is practical for disinfectants, solvent blends, flavor extracts, and rinse solutions. Because measurements are volumetric, . The calculator standardizes units so a 250 µL addition and a 10 mL make-up volume can be compared consistently.

Inputs, units, and built-in checks

Each volume can be entered in µL, mL, or L. Internally, all values are converted to milliliters to avoid unit drift. Validation prevents negative volumes, totals of zero, and cases where the solute exceeds the stated total. These rules reduce transcription errors when copying from notebooks, labels, or SOP sheets used during preparation and QC sign-off.

Reverse modes for planning targets

Besides computing percent from measured volumes, the tool can solve for unknown solute, total, or both when a target percent is known. For example, if you need 70% v/v at 500 mL total, the solute is 350 mL and the remainder is solvent. If solvent volume is fixed, the tool back-calculates the total and solute needed to reach the specified fraction.

Interpreting results and the Plotly chart

The result card reports v/v% plus solute, solvent, and total volumes in a consistent unit. The Plotly visualization summarizes composition as a stacked bar and a pie chart so the fraction is obvious at a glance. This helps during training, batch reviews, and quick comparisons across runs. You can still record the numeric values for traceability.

Precision limits and laboratory reality

Many mixtures show slight volume contraction or expansion after mixing, especially with alcohol–water systems. The calculator assumes ideal additivity, which is acceptable for planning and quick checks. For regulated or high-accuracy work, verify the final volume after mixing or use density-based methods. Document instrument class, temperature, and mixing protocol in your record.

Good documentation habits for repeatable batches

Exporting CSV supports spreadsheet logs, while the PDF produces a clean attachment for electronic lab notebooks. Record the selected mode, input units, and displayed precision so results can be reproduced later. When scaling, keep the percent constant and multiply the target total volume. Using consistent rounding rules across teams improves comparability during audits and investigations.