Dilution Calculator
Enter your stock concentration and the concentration and volume you want to make to find how much stock to use and how much diluent to add.
Result
Stock solution to use
10.0 mL
Diluent to add
90.0 mL
Make the solution up to 100 mL total volume.
Dilution factor: 10×
The stock is 10× more concentrated than the final solution.
No dilution is needed. The stock already has the target concentration.
Calculation working
Calculate the stock volume
Find the stock volume
V₁ = (C₂ × V₂) ÷ C₁
V₁ = (0.10 M × 100 mL) ÷ 1.00 M
V₁ = 10.0 mL
Find the diluent volume
Diluent = final volume − stock volume
100 mL − 10.0 mL = 90.0 mL
Diluent = 90.0 mL
Take 10.0 mL of stock and add diluent until the total volume reaches 100 mL.
Dilution factor
10×
1.00 ÷ 0.10 = 10×
Dilution factor = C₁ ÷ C₂
or equivalently: Dilution factor = V₂ ÷ V₁
The dilution factor shows how many times the stock is more concentrated than the final solution. For 1.00 M → 0.10 M, the factor is 10×.
Why does C₁V₁ = C₂V₂ work?
During a simple dilution, you add diluent without adding more solute.
The amount of solute stays the same, so C₁V₁ = C₂V₂. The concentration decreases because the same amount of solute is spread through a larger total volume.
What does a dilution calculator do?
It tells you how much stock solution and diluent you need to make a solution at a lower concentration.
Stock vs target concentration
Stock concentration
The concentration of the solution you start with.
Target concentration
The concentration you want after dilution.
1.00 M stock → 0.10 M target
The stock is 10 times more concentrated than the target.
The dilution formula
C₁V₁ = C₂V₂
- C₁
- = stock concentration
- V₁
- = stock volume
- C₂
- = target concentration
- V₂
- = final volume
V₁ = (C₂ × V₂) ÷ C₁
Approximate diluent volume = V₂ − V₁
Examples
Calculation examples
1.00 M → 0.10 M → 100 mL
10.0 mL stock
90.0 mL diluent
5.00 M → 0.50 M → 1 L
100 mL stock
900 mL diluent
10 mM → 2 mM → 250 mL
50.0 mL stock
200 mL diluent
10 % w/v → 2 % w/v → 500 mL
100 mL stock
400 mL diluent
Scope
What this calculator handles
It handles:
- Simple one-step dilution
- Stock concentration
- Target concentration
- Stock volume
- Final volume
- Diluent volume
- Dilution factor
- Compatible concentration units
- µL, mL, and L volume units
- Solving for any one missing value
Use another Chemistry Inspect tool for:
FAQ
Frequently asked questions
What is the dilution formula?
The standard dilution equation is C₁V₁ = C₂V₂. It relates the stock concentration and volume to the final concentration and total volume.
How much stock solution do I need?
Use V₁ = (C₂ × V₂) ÷ C₁. The calculator does this automatically.
How much water or diluent should I add?
Subtract the stock volume from the final volume: Diluent = V₂ − V₁. For example, 10 mL stock in a 100 mL final solution requires 90 mL of diluent.
Does the final volume include the stock solution?
Yes. Final volume is the total volume of the finished solution, including the stock solution. For 10 mL stock and a 100 mL final volume, add diluent until the total volume reaches 100 mL.
Can I use mM, µM, or nM?
Yes. The stock and target concentrations must use compatible units. The calculator handles conversions between common molar units.
Can I use percentages?
Yes, when the stock and target use the same type of percentage concentration, such as % w/v with % w/v.
Can I dilute a solution to a higher concentration?
No. A simple dilution lowers concentration. To make a higher-concentration solution, you need a more concentrated stock or a different preparation method.
What is the dilution factor?
The dilution factor tells you how many times the stock concentration is reduced. Dilution factor = C₁ ÷ C₂.
What is the difference between stock volume and final volume?
Stock volume is the amount of concentrated solution you take. Final volume is the total amount of solution after adding diluent.
Does this calculator work for serial dilutions?
No. This calculator handles one dilution step. A serial dilution requires multiple sequential dilution steps.