CatFACS is a standardized system that requires certification to use. The CatFACS Manual identifies each muscle movement that causes visible changes in facial appearance. These are called Action Units (AUs) and each AU is listed in the manual with a numerical code. For each AU, the muscular basis is described along with a list of observable appearance changes and subtle differences between AUs.


The CatFACS Manual and the CatFACS Test are freely available through this website. Please contact us for the passwords. We keep a record of who is using the system so we can maintain standardisation.


For a correct visualization of the CatFACS Manual, please install the latest version of Adobe Reader on your computer. To decompress the files (manual and test), please install WinRar.


Click here to download the CatFACS manual.







To use the system you need to take a test after training. This ensures that all users are coding in the same way, and so maintains the standardisation of the system.


To access the CatFACS Test clips click here.








How to use CatFACS?



After becoming CatFACS certified, the coder will be able to reliably code facial movements in videos and pictures of cats. High quality close-ups of the face should ideally be recorded and pictures must be compared with the neutral face of each cat, accounting for individual variation. Depending on the purpose of coding, two or more cameras should be used in synchrony (e.g. one camera zoomed in on the face and other camera recording body and context behaviours).


The CatFACS can be applied to investigate communication and emotion in cats through the analyses of the individual facial behaviour.


Department of Psychology

University of Portsmouth