Using the Feline Grimace Scale
January 29, 2026
Ellen Vogel, CFMG, CFVP, Elite FFCP (Veterinary)
The purpose of the Feline Grimace Scale (FGS) is to assist owners, veterinary professionals, and other cat service providers in determining if a cat may be in pain. For veterinary professionals, it also allows them to score the pain to determine the cat’s needs for pain medication.
Cats are masters at masking pain. We usually think of cats as predators, hunting small rodents and bugs around our homes or the environment they live in. Cats are actually in the middle of the food chain, being prey to larger animals. They instinctively know that injury and showing weakness may make them a target for their predators. As a result, they will hide their pain until it is severe. These instincts hamper our ability to know when our cats are sick or in pain. Using proven tools, including the FGS, helps us to detect illness and adequately care for our cats when they are not feeling their best.
The study that resulted in the FGS was conducted at the University of Montreal veterinary teaching hospital. Videos of cats were taken and observed by multiple researchers to compare results. Cats that were identified as being in pain were treated and, in some cases, videos were taken after treatment to compare results. In this way, the FGS was “validated,” meaning results were repeatable both over time and by different researchers in determining what it was intended to evaluate: pain.
The result of this work is an app that can be installed on our phones. You can view information about this app on its website: https://www.felinegrimacescale.com/
The app provides a method for the user to determine a cat’s pain score by observing and scoring separately the positioning of the cat’s ears, eyes, muzzle, whiskers, and head. Each of these body parts is ranked 0, 1 or 2. The rankings are added together for the cat’s total pain score. If the score is less than 4, the cat is considered pain-free or in minimal pain. A score of 4 or higher indicates the cat’s pain should be assessed by a veterinary professional, and the pain treated as deemed necessary by the veterinarian.
The menu at the bottom of the home screen has options to return to Home, Learn, Score, and has a section “About the app.” The “Learn” option allows you to look at both photographs and drawings of each of the body parts you will be ranking at each step. For example, if you look at the photos and drawings for the eyes, you will see them wide open and round for a rank of 0, partially closed for 1, and almost closed for 2. The instructions also state to rank the eyes 1 if you are unsure. View examples comparing a photo of a cat to the matching grimace scale drawing here: https://www.felinegrimacescale.com/app-landing-page
The “Score” menu option allows you to score a specific cat’s pain level. Note the instructions to observe the cat while awake, but do not disturb the cat. If the cat is actively doing anything, such as eating or grooming, wait until the cat is finished to begin your evaluation.
As you move through the screens for each of the body parts, you will click on the photo and drawing combination that best matches your cat’s position. By using the app and clicking on the photos/drawings, you do not have to keep track of and add your score.
Once you finish ranking the positions of the body parts, a score will be shown. At this point you may also take a photo of your cat that can be shared with the veterinary professional you will be consulting. Having a photo of what the cat looked like at home can be very helpful. When you take the cat to the veterinarian, they will probably have adrenaline ramping up their body. No longer relaxed or in their own home environment, they are more apt to try to hide their pain, making a true assessment more difficult in the clinic setting.
If your cat is in pain, it is important to follow up with your veterinarian. Whether it is a short-term or long-term problem, your veterinarian can help you determine the best way to keep your cat comfortable. While medical treatment for cats in pain remains behind that for dogs, modern studies and medical advances have brought new medications to the market specifically for treating cats in pain, so there is no reason for a cat to suffer needlessly.
A veterinarian who was treating one of my cats with comorbidities recommended a treatment for her arthritis. The medication had the side effect of making most cats sleepy. I expressed my concern with this, and her answer gave me pause to think. She said I could choose to not treat her arthritis, and she would continue to be in pain. If I did choose to treat her, she might sleep nineteen or twenty hours a day instead of eighteen. But during those four or five hours she was awake, she would feel much better and be more apt to eat, drink, and enjoy other normal cat activities such as playing or being petted. Of course, I opted to treat her pain. She was able to do more, and she lived a more comfortable and happier life because of the treatment.
References:
Evangelista, M.C., Watanabe, R., Leung, V.S.Y. et al. Facial expressions of pain in cats: the development and validation of a Feline Grimace Scale. Sci Rep 9, 19128 (2019). https://doi.org/10.1038/s41598-019-55693-8
Evangelista, M.C., Steagall, P.V. Agreement and reliability of the Feline Grimace Scale among cat owners, veterinarians, veterinary students and nurses. Sci Rep 11, 5262 (2021). https://doi.org/10.1038/s41598-021-84696-7
Monteiro BP, Lee NH, Steagall PV. Can cat caregivers reliably assess acute pain in cats using the Feline Grimace Scale? A large bilingual global survey. Journal of Feline Medicine and Surgery. 2023;25(1). https://doi.org/10.1177/1098612X221145499