Use this dilution calculator to solve C1V1 = C2V2 for stock concentration, stock volume, target concentration, or final volume, then review dilution factor.
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Scope
This page applies the standard C1V1 = C2V2 dilution relation for the same solute system. It does not convert
between unlike concentration definitions or calculate density corrections.
Enter the stock concentration, stock volume, and target concentration Enter the three known values above to solve the missing dilution term.
A dilution calculator solves the standard stock-to-target relation C1V1 = C2V2. This page also explains the main assumptions behind the dilution planning with c1v1 = c2v2 result, highlights the supporting figures shown by the calculator, and helps the reader use the estimate without overstating what a quick online tool can prove.
What the dilution equation assumes
The classic dilution equation states that the amount of solute stays constant before and after dilution, so concentration times volume is conserved: C1V1 = C2V2.
That means the page is appropriate when you are making a lower-concentration solution from a stronger stock of the same substance and the same concentration basis.
C1V1 = C2V2
Relates stock concentration and transferred stock volume to target concentration and final prepared volume.
Dilution factor = C1 / C2 = V2 / V1
Shows how many times the stock is diluted between the starting and final solution.
When this page is the right tool
Use it for same-solute dilutions such as preparing 100 mL of 0.10 M solution from a 1.00 M stock, or scaling a micromolar working solution from a stronger master stock.
Do not use it to convert between unrelated concentration definitions, density-based systems, or formulations where molarity and mass concentration are mixed without the extra assumptions needed to bridge them.
From calculator result to bench preparation
A useful C1V1 C2V2 calculator should not stop at the missing variable. In everyday lab work, the next question is usually how much stock to transfer and how much diluent to add before mixing to the final volume.
That is why the calculator shows a preparation plan, dilution factor, stock share, diluent share, and solvent-to-add volume. Those outputs help distinguish the stock aliquot from the final total volume, which is one of the most common mistakes in dilution problems.
Pipetting checks for tiny aliquots
High dilution factors can produce stock transfer volumes that look correct mathematically but are hard to pipette accurately. A 1:1000 dilution into a small final volume may require a sub-microlitre transfer, which is often less reliable than preparing an intermediate dilution.
When the calculated transfer is very small, treat the warning as a planning cue. Increase the final volume, use an appropriate pipette range, or make a staged working stock before preparing the final solution.
Simple dilution versus serial dilution
This page solves a one-step dilution: one stock solution, one target concentration, and one final volume. A serial dilution calculator is different because it designs a stepwise series where each tube or well becomes the source for the next dilution.
For a single working solution, C1V1 = C2V2 is usually the right tool. For multi-point standard curves, microbiology plates, assay calibration, or repeated 1:10 steps, use the single-step result as a building block and document each transfer separately.
Worked example
Suppose the stock is 1.00 M, the target concentration is 0.10 M, and the final volume is 100 mL. Rearranging C1V1 = C2V2 gives V1 = (C2 × V2) / C1, so the required stock transfer is 10 mL.
The remaining 90 mL is solvent or diluent added to reach the final prepared volume of 100 mL.
Frequently asked questions
Why does the page reject a target concentration above the stock concentration?
Because that is no longer a dilution. If the target concentration is greater than the stock concentration, you would need a concentration or solvent-removal step instead of a simple stock-plus-diluent preparation.
Can I mix units like M and mM?
Yes. This calculator normalizes the supported molarity units internally before solving. The result is then shown back in your selected display units for each side of the equation.
Does this page tell me which solvent to use?
No. It only solves the volume-concentration relation. Solvent compatibility, stability, temperature effects, and final matrix constraints still depend on the chemistry of the system you are preparing.
How do I calculate how much diluent to add?
First solve for the stock volume V1, then subtract that stock aliquot from the final volume V2. For example, 10 mL of stock brought to 100 mL final volume means 90 mL of diluent is added.
What is the difference between dilution factor and dilution ratio?
Dilution factor usually describes the final volume divided by the stock aliquot, such as 10×. A ratio such as 1:10 often means 1 part stock in 10 total parts, although some protocols use ratio language differently, so check the method wording.
When should I make an intermediate dilution?
Make an intermediate dilution when the calculated stock transfer is too small for reliable pipetting, when the dilution factor is very large, or when a protocol requires staged preparation for accuracy.
Can this calculator handle serial dilutions?
It solves one dilution step at a time. You can use it for each step in a serial dilution, but a dedicated serial dilution table is better when you need many repeated tubes or wells.
