Accurate cell counts in just a few seconds

Thermo Fisher Scientific offers two high-performance automated cell counters designed to meet the needs of any lab. Choose from simple brightfield counting with the Invitrogen Countess II Automated Cell Counter or the flexibility and upgradability of fluorescence detection with the Invitrogen Countess II FL Automated Cell Counter.

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Both automated cell counters offer these benefits:

Accuracy—eliminate the subjectivity of manual cell counting and minimize user-to-user variability
Speed—count live and dead cells and measure viability and average cell size in as little as 10 seconds
Convenience—a capacitive touchscreen and simple user interface provides quick startup and requires minimal training

Compare Countess II and Countess II FL Automated Cell Counters

  Fast, easy, affordable brightfield counting

Countess II
Automated Cell Counter

Fluorescence counting with color options

Countess II FL
Automated Cell Counter

Sample results
Counting mode Brightfield Brightfield
Two optional, user-changeable fluorescent channels (>20 fluorescent light cubes to choose from)

Disposable slides

Reusable slide and
disposable slides
Focus Autofocus with manual focus option
User interface Intuitive touch screen with ability to use a mouse, if desired
Processing time <10 seconds
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Advanced autofocusing and counting algorithms

The Countess Automated Cell Counter contains advanced autofocusing and counting algorithms to allow you to quickly and accurately identify and count cells within a population (Figure 1). Countess instruments are compatible with a broad range of cell types and cell lines, and we have validated their use on a number of commonly used cell lines. Upon insertion of the slide the Countess instrument will automatically focus on cells, which helps to minimize user variation associated with manual focusing. Cells between ~7 µm and 60 µm and in suspension at a density of 1 x 104 to 1 x 107 cells/mL are optimal for counting.

graph showing accurate cell counts using the Countess II Automated Cell Counter  

Figure 1. Autofocusing and advanced counting algorithms are designed for more precise counting.
NIH/3T3, HeLa, and HL-60 cells were counted using a Countess II FL Automated Cell Counter (blue bar) or counted manually under a microscope using a hemocytometer (purple bar). Each bar is an average of 10 counts.


Clumpy cells are not a problem

Clumpy cells are not a problem for the Countess Automated Cell Counter. Whether you currently use automated or manual cell counting methods, obtaining accurate cell counts from samples containing clumpy cells can be difficult. The advanced counting algorithms of the Countess Automated Cell Counter can clearly identify cell boundaries within clumps of cells, resulting in accurate cell counts (Figure 2).

screenshot of Countess II FL counting clumpy cells

Figure 2. Accurate cell counts, even with clumpy samples.
The segmentation and counting algorithms of the Countess II FL Atuomated Cell Counter are able to resolve clumps of cells in this NIH/3T3 cell sample.

Easily gate cells and view histograms

Cells can be easily gated based on cell size, brightness, and circularity. View the histogram by selecting the graph icon and watch the changes in real time as you use the gating features. The average cell size is also displayed on the histogram.


Save profiles for customized settings

Custom profiles, including settings for cell size, brightness, and circularity can be saved and named for easy retrieval from the capture and results screens.


Featured application note: Cell culture quality control during T cell expansion

See how the Countess II Automated Cell Counter provides fast, accurate measurements of T cell viability and concentration both after initial isolation and activation, even when Dynabeads Human T-Activator CD3/CD28 is present.

Download application note