Dilution Calculator
How It Works
The dilution equation C1V1 = C2V2 is one of the most useful formulas in chemistry and biology. It relates the concentration and volume before dilution (C1, V1) to the concentration and volume after dilution (C2, V2). You can solve for any one unknown if you know the other three values.
To use this calculator, enter three known values and set the unknown to 0. The calculator will solve for the missing variable. The most common use is finding how much stock solution (V1) you need: V1 = (C2 x V2) / C1.
This equation works for any concentration unit (M, %, mg/mL, etc.) as long as C1 and C2 use the same units, and V1 and V2 use the same units. Remember that dilution only increases volume and decreases concentration — you cannot concentrate a solution by dilution.
Frequently Asked Questions
How do I dilute a 10M solution to 1M?
Using C1V1=C2V2: V1 = (1M x desired volume) / 10M. For 100 mL of 1M solution, you need 10 mL of the 10M stock, diluted to 100 mL total with solvent.
What does a 1:10 dilution mean?
A 1:10 dilution means 1 part sample to 9 parts diluent (10 parts total). The concentration is reduced to 1/10th of the original. This is equivalent to adding 1 mL of sample to 9 mL of diluent.
Can I use this equation for serial dilutions?
Yes, apply C1V1=C2V2 to each dilution step. For a 1:10 serial dilution, each step reduces concentration by 10x. Three steps of 1:10 give a total dilution of 1:1000.
Does temperature affect dilution calculations?
The equation itself is temperature-independent, but solution volumes change slightly with temperature. For precise work, prepare dilutions at the temperature specified in your protocol.