Free Cell Counter
Tap a square each time you count a cell in that Neubauer large square. Enter your dilution, then read cells per millilitre. This assumes an Improved Neubauer chamber (0.1 mm depth). It is a calculator, not a medical device.
How to use the cell counter
This calculator is for an Improved Neubauer hemocytometer. You count cells under the microscope, tap the matching square here, enter the dilution you actually used, and read cells per millilitre. It does not look through a camera. It does not replace lab SOP.
- Load the chamber as your lab protocol requires and let cells settle.
- Count cells in each of the five large squares you plan to use (four corners and the centre is a common pattern).
- Tap + on Square 1 through Square 5 to match those counts. Use – if you over-tap.
- Set Dilution factor to the final dilution of the sample in the chamber, including any stain mix.
- Read cells/mL. Reset count before the next sample.
The formula this page uses
A standard large Neubauer square is 1 mm by 1 mm with a chamber depth of 0.1 mm, so the volume of one large square is 0.1 mm3, which is 10-4 mL. Wikipedia’s hemocytometer article and INTEGRA’s cell counting explainer use that geometry.
This page computes: (average cells per large square) × (dilution factor) × 10,000 = cells/mL. Average is the total of the five squares divided by 5. If you only counted three squares, put 0 on the unused squares only if you also change the math. In this first version the average always divides by 5, so use all five squares or scale on paper.
Viability with trypan blue is a separate count of live versus dead cells. This version does not split those two populations. Count viable cells only if you need a viable concentration, or keep live and dead on paper and apply the same formula twice.
| Input | What to enter | Source |
|---|---|---|
| Square 1 to 5 | Raw cell counts from large squares | Your microscope |
| Dilution factor | Final dilution in the chamber | Your protocol |
| 10,000 | Fixed for Improved Neubauer 0.1 mm depth | Chamber geometry |
What this first version does not do
- No camera, no automated image count, and no other chamber types (Bürker, Fuchs-Rosenthal).
- No viability split inside the widget.
- Not a diagnostic or medical device. Follow your lab’s validated method.
If you only need a click tally with no concentration math, that is the homepage clicker. Background reading: cell counter article.