Hemocytometer app

I have talked before about an iPhone app called HemocyTap. I have been using it for a while and I fully recommend it. It’s a total time saver. No going around the lab trying to find the tally counters, the lab book (or a piece of paper), the calculator… Plus, you get all your data directly in your inbox! It’s all in there, and it’s as easy as ABC. So if you’re starting out with the hemocytometer, this app can save your life. Or, if you’re experienced already, you will ask yourself how you have survived so long without it. Seriously.

*UPDATE* The new HemocyTap version has been released! Here’s the video:


*OLD VERSION* These guys just posted a fun video that quickly explains its capabilities; I personally think it’s awesome!

The following two tabs change content below.
I did my PhD in the Department of Chemical Engineering at Imperial College London. My research focused on mathematical modeling of the cell cycle in leukemia and involved experiments with cell lines. During that time, I had to count cells with a hemocytometer so often to track growth that I got tired and decided to build an app, HemocyTap, and share my knowledge on the topic here to help as many people as possible.

Latest posts by Maria Fuentes, PhD (see all)

16 comments on “Hemocytometer app

  1. […] Hemocytometer app […]

  2. […] volume. Get all the calculation below done for you and read the volume you need to add. Check here for a detailed video on how to do […]

  3. How about an app for Android?

  4. […] Hemocytometer app […]

  5. […] Hemocytometer app […]

  6. The app is giving me different results compared to the online calculator. Any idea of what might be going on?

    • Hi Jimmy,

      There are a few things that work differently in the app. For instance, you have the dilution instead of the dilution factor. The dilution, in the format 1:x (where 1 is the parts of cell suspension and x the parts of dilutant, usually PBS), is equivalent to the dilution factor using the formula: dilution factor = (1+x). So if you’re using for instance 1:1 in the app, you should be using a dilution factor of 2 in the online calculator.

      The other thing to double check is that the number of highlighted squares in the app corresponds to the number of squares counted in the online calculator. For example, let’s say you have counted cells in the four corner squares of two hemocytometer chambers. In the app, they would be highlighted in blue and the cell numbers you have counted would appear on top. In the calculator, you need to enter 8 (4 + 4) in the # squares counted field. Finally, for the online calculator you should select “Big squares in the corner”.

      Let me know if you still get different results and I will look into it in more detail.



      • Hi Maria,

        Thanks for the quick response! I didn’t know that you need to un-highlight squares that are not being used from the settings. That fixed my problem.

        I noticed that in the “Subculture” part of the app, the “Volume to add” actually gives you the total volume – it doesn’t subtract the initial volume as explained here: http://www.hemocytometer.org/2013/04/09/hemocytometer-calculation/

        Can you confirm this, or am I missing something there?


        • Hi Jimmy,

          Glad you got it working.

          Yes, that is correct. The app assumes you remove the supernatant (used medium) before adding new medium, and therefore gives you the total amount of new medium to add. If you usually keep the old medium and add new medium to it, then you are right that you should add the “volume to add” – “initial volume”. I will keep it in mind for future versions of the app.

          Thanks for your suggestion!


  7. A good help.thanks

  8. Hello.
    Considering how thick the hemocytometer slide is, one would imagine it being difficult to view cells on the hemocytometer with an inverted microscope. However, this is not the case. I was wondering if you had any information about the optical properties of the hemocytometer slide. I looked online but did not get any information on this topic. Thanks.

    • Hi Paul,

      I didn’t find any specific information on the topic either, but I would assume adjusting the focus by moving the plate closer to the lens corrects for the increased distance between the lens and the hemocytometer surface. Here are a couple of answers that may help: stackexchange, researchgate.



  9. Hi Maria

    I wanted to know if you could recommend a good microscope for YEAST cell counting and viability with a haemocytometer. The microscope must have the ability to fit a camera and ideally the scope would be supplied without the camera. We offer very sophisticated methods at present with a disposable haemocytometer but for the small breweries we are thinking of a low cost solution involving a good quality microscope..

    Dr John Carvell
    Aber Instruments http://www.aberinstruments.com

Leave a Reply

Your email address will not be published. Required fields are marked *