Calculate cell viability percentage and estimated cells per mL from trypan blue hemocytometer counts, number of squares, and dilution factor.
Enter live and dead trypan blue counts to estimate viability and cells per mL
Trypan blue is a vital dye that cannot penetrate the intact cell membrane of living cells. When mixed with a cell suspension:
This makes it easy to distinguish viable from non-viable cells under a microscope.
Viability is expressed as the percentage of live cells relative to total cells:
Where Total Cells = Live + Dead (trypan blue–positive) cells counted.
A hemocytometer is a specialized counting chamber with a defined geometry:
This gives the standard conversion factor of 10⁴:
The dilution factor accounts for how much you diluted your original sample before loading the hemocytometer. For example:
Include all dilutions between the original sample and the counting chamber.
This tool is for research and educational purposes only. Results are approximate and depend on accurate counting and dilution. Always follow your lab's SOPs, biosafety guidelines, and reagent instructions. This tool does not provide experimental protocols, plating strategies, or clinical guidance.
Convert OD600 to cell density for bacterial cultures
Estimate cell doubling time and generate growth curves
Calculate cells needed for plates, flasks, and dishes
Plan serial dilutions and calculate CFU/mL
Plan stock to working solution preparation
Calculate multiplicity of infection for viral transductions
Quickly estimate viability and cell concentration for your research planning
Explore All Biology Calculators