Viable Cell Count Calculator

When working with cell cultures, the Viable Cell Count Calculator uses the trypan blue exclusion method to determine how many live cells are present in your suspension. Enter your viable (unstained) cell count, dead (stained) cell count, number of large squares counted, dilution factor, and hemocytometer factor to get your cell viability percentage, viable cell concentration, total cell concentration, and total viable cells. Optionally, enter your original suspension volume to calculate the absolute number of viable cells in your full sample.

Total number of bright, unstained cells counted across all selected squares

Total number of blue-stained cells counted across all selected squares

How many large (1mm x 1mm) squares were counted on the hemocytometer grid

Factor by which suspension was diluted before counting (typically 2 for trypan blue)

Factor to convert average cells/square to cells/mL (default 10,000)

mL

Optional: Total volume of the original cell suspension

Results

Cell Viability

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Viable Cell Concentration

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Total Cell Concentration

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Total Viable Cells

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Frequently Asked Questions

What is the trypan blue exclusion method?

Trypan blue is a vital dye that cannot penetrate healthy cell membranes but enters dead or damaged cells, staining them blue. Viable cells remain unstained and appear bright under the microscope.

Why do I need to count multiple squares on the hemocytometer?

Counting multiple squares (typically 4 or 5) provides better statistical accuracy and reduces counting error. It gives a more representative sample of your cell suspension.

What dilution factor should I use with trypan blue?

The standard dilution factor for trypan blue staining is 2:1 (equal volumes of cell suspension and 0.4% trypan blue), giving a dilution factor of 2.

What is considered good cell viability?

Generally, >90% viability is excellent, 80-90% is good, 70-80% is fair, and <70% is poor. However, acceptable viability depends on your specific application and cell type.

How is the hemocytometer factor calculated?

The standard hemocytometer factor is 10,000 (1×10⁴), which converts the average cells per large square to cells per mL, accounting for the chamber's volume and dimensions.

Can this calculator be used for different cell types?

Yes, this calculator works for any cell type that can be stained with trypan blue, including mammalian cells, yeast, and some bacterial cells.

What if I counted a different number of squares?

The calculator accounts for the number of squares counted in its calculations. You can select 1, 4, or 5 squares depending on your counting method.