How to Use the Working Solution Calculator
Enter your stock concentration (C1), desired working concentration (C2) and final working volume (V2). Click Calculate to get the exact volume of stock to add and the volume of diluent required. The visual bar shows the ratio of stock to diluent at a glance.
The Working Solution Formula
Diluent volume = V2 − V1
C1 = stock concentration | C2 = working concentration | V2 = final total volume | V1 = volume of stock to add
Common Working Solution Examples
V1 = (1 × 500) / 10 = 50 mL stock
Diluent = 450 mL water
V1 = (50 × 100) / 1000 = 5 mL stock
Diluent = 95 mL water
V1 = (0.1 × 200) / 10 = 2 mL stock
Diluent = 198 mL
V1 = (1 × 50) / 100 = 0.5 mL stock
Diluent = 49.5 mL
About Working Solutions in the Laboratory
A working solution is the final, ready-to-use concentration of a reagent used directly in an experiment. It is typically prepared fresh from a concentrated stock solution immediately before use. This approach keeps stock solutions stable for longer and reduces waste.
Common examples include preparing 1× running buffer from 10× stock, diluting antibodies for Western blot or ELISA, preparing DMSO drug dilutions for cell assays and making working concentrations of enzyme substrates or inhibitors.