How It Works
This calculator works in 4 steps.
Enter counts per square
Type the cell counts for each large square counted.
Enter the squares counted
Type the number of squares, such as 4 corner squares.
Enter the dilution factors
Type the trypan blue factor (2 for 1:1) and any predilution factor.
Read cells/mL
The calculator averages counts and returns cells/mL and total cells for a stated volume.
The Formula
The formula multiplies the average count per square by the dilution factor and 10⁴.
cells/mL = avg count × DF × 10⁴N = cells/mL × V_sample% viable = 100 × live / (live + dead)- avg count:
- Mean cells per large square
- DF:
- Product of all dilutions before counting
- 10⁴:
- Chamber factor (1 / 0.1 µL)
An average of 50 cells per square after a 1:1 trypan blue mix gives 50 × 2 × 10⁴ = 1.0 × 10⁶ cells/mL.
Conversion Table
The conversion table converts 6 average counts and dilution factors into cells/mL.
| Average per square | Dilution factor | Cell density |
|---|---|---|
| 50 | 2 | 10⁶ cells/mL |
| 85 | 2 | 1.7 × 10⁶ cells/mL |
| 32 | 1 | 3.2 × 10⁵ cells/mL |
| 120 | 5 | 6 × 10⁶ cells/mL |
| 45 | 10 | 4.5 × 10⁶ cells/mL |
| 25 | 2 | 5 × 10⁵ cells/mL |
What Is the Hemocytometer Dilution Correction Calculator?
The Hemocytometer Dilution Correction Calculator is a tool that converts the average count per large square of a hemocytometer into cells per mL, corrected for any dilution made before counting. Each large square of a standard Neubauer hemocytometer holds 0.1 µL (10⁻⁴ mL).
Counting samples are often mixed 1:1 with trypan blue, a dilution factor of 2. Dense samples are prediluted further to keep counts within 20 to 100 cells per square. The calculator multiplies the average count by the counting chamber factor of 10⁴ and by every dilution factor applied.
Common Uses
There are 5 main uses of this calculator.
Routine cell counts
Cell culture staff count before passaging.
Viability checks
Users count live and dead cells with trypan blue.
Blood cell counts
Labs count leukocytes after diluting blood.
Yeast counts
Brewers count yeast before pitching.
Semen analysis
Andrology labs count sperm after dilution.