Hemocytometer Cell Count Calculator
Calculate total cell concentration, live cell concentration, and viability percentage from hemocytometer (Neubauer chamber) counts using trypan blue exclusion.
Hemocytometer Cell Count
basicCalculate cell concentration and viability using a hemocytometer
Formula
Cells/mL = (cells/grids) × dilution × 10⁴
How It Works
The hemocytometer (Neubauer chamber) is a specialized microscope slide with a precise grid for counting cells. The grid has 9 large squares, each with an area of 1 mm² and a depth of 0.1 mm, giving a volume of 0.1 µL per square.
Cells/mL = (cells counted / grids) × dilution factor × 10⁴
Viability (%) = live cells / (live + dead) × 100
The factor of 10⁴ converts the volume of one grid square (0.1 µL) to 1 mL.
Example
You count 80 live cells and 20 dead cells across 4 grid squares with a 2× dilution (trypan blue mix):
Total cells = 80 + 20 = 100
Total cells/mL = (100/4) × 2 × 10⁴ = 500,000 cells/mL
Live cells/mL = (80/4) × 2 × 10⁴ = 400,000 cells/mL
Viability = 80/100 × 100 = 80%
Frequently Asked Questions
How many cells should I count per grid?
Aim for 30-300 cells per grid square for statistical accuracy. If too crowded (>>300), dilute your sample. If too sparse (<30), concentrate or count more grids.
What is a good viability percentage?
For most cell culture work, viability above 90% is excellent, 80-90% is acceptable, and below 70% indicates significant cell stress or death.
Should I count cells on the border lines?
Standard practice: count cells touching the top and left borders, exclude those touching bottom and right borders. This prevents double-counting between adjacent squares.