Feline Grimace Scale: How to Read Your Cat’s Pain Signals

The Feline Grimace Scale helps cat owners recognize acute pain, understand facial changes, and decide when to call their veterinarian today. A low score cannot rule out illness, and this tool cannot identify the cause of pain or assess chronic pain.

Feline Grimace Scale guide: two owners calmly watching their cat resting on a rug
AI-generated editorial illustration of owners observing their cat; not a clinical pain-scoring example.

What does the Feline Grimace Scale actually measure?

Maybe your cat has stopped coming to the kitchen, or their face looks different after a procedure. You want something more useful than guessing whether they look unhappy. The Feline Grimace Scale, often shortened to FGS, gives you a structured way to look for facial changes associated with acute pain.

Researchers at the Université de Montréal developed the tool around five features: the ears, eyes, muzzle, whiskers, and position of the head. In the original 2019 validation study, scores distinguished cats with naturally occurring acute pain from controls and decreased after pain relief.

Acute pain can follow an injury or surgery, but it can also accompany an illness. The score does not tell you whether a cat has a urinary blockage, a sore mouth, an abdominal problem, or something else. That takes a veterinary examination and, sometimes, tests.

Think of your observations as information to bring to the appointment. For the bigger picture—including changes in movement, appetite, and interaction—see our guide to recognizing signs of pain in cats.

When should you skip the scale and seek urgent care?

Do not wait for a high score when your cat has an emergency symptom. Contact an emergency veterinary hospital right away for difficulty breathing, collapse, a major injury, or suspected poisoning. Call ahead when you can without delaying care.

Repeated trips to the litter box with straining and little or no urine also need immediate veterinary attention. Cornell identifies urethral obstruction as a medical emergency. A cat's face cannot safely rule it out. Our explanation of constipation versus a urinary blockage explains why these situations can be confused.

Breathing trouble deserves the same urgency. Cornell's breathing guidance advises immediate veterinary help when a cat cannot breathe comfortably. Do not spend time taking pictures, calculating a score, or trying a home remedy first.

How do you use the Feline Grimace Scale at home?

Start with the official practice guide and training images. They are much more useful for learning the expressions than a description alone. This article explains the decisions around scoring; it does not replace that visual training.

  1. Watch an awake, undisturbed cat for about 30 seconds. Give them space. You should not need to hold them, touch a sore area, or make them react.
  2. Wait until eating, grooming, playing, or vocalizing has stopped. Those activities change the face. Do not wake a sleeping cat just to score them.
  3. Look at each of the five features. Use the official examples to decide whether the pain-related change is absent, uncertain or moderately present, or clearly present.
  4. Record the observation and the context. Note the time, behavior, and any medication already given as prescribed.

Good lighting helps. If you cannot see the muzzle or whiskers, write that down rather than moving the cat around for a better angle. A partly hidden face is an incomplete observation, not a reassuring result.

What are the five facial signs of pain in cats?

Each feature is called an action unit in the research. You do not need to memorize that term. You do need to check all five rather than deciding everything from one ear position.

Ears: are they upright or turning outward?

In the official examples, ears facing forward receive 0 for this feature. Ears beginning to spread apart fit the middle category. More obvious flattening and outward rotation fit 2. Check the reference pictures before assigning a number: an ear turning toward a sound is not, by itself, a diagnosis of pain.

Eyes: are they open or persistently narrowed?

The feature called orbital tightening means narrowing around the eyes. Open eyes fit 0; partial narrowing fits 1; obvious squinting fits 2. Score while the cat is awake and settled, not during a blink or a nap. A new eye problem needs its own veterinary assessment, even if the other features look ordinary.

Muzzle: does the area around the nose and mouth look tense?

A relaxed, rounded muzzle is the 0 reference. Mild tension fits 1; a clearly tightened, more stretched-looking muzzle fits 2. This is one of the harder features for owners to judge. Compare with the official images, and describe your uncertainty honestly. Do not squeeze or lift the lips to try to make the feature easier to see.

Whiskers: are they loose or straighter and pushed forward?

Relaxed whiskers usually look curved. As the scored change becomes more apparent, they can look straighter and directed forward. The reference categories progress from 0 to 2. Whiskers can be difficult to see against dark fur or a busy background; poor visibility should not become an automatic zero.

Head: is it held above or below the shoulder line?

The official reference moves from a head held above the shoulders, through roughly level with them, to a lowered or downward-tilted head. Context matters: these are observations of an awake cat at rest. Reaching for food, sniffing the floor, or settling down to sleep is not the same observation.

The official training manual shows the differences. We have linked to it rather than recreating the scale with generated cats, which could teach the wrong visual cues.

What does a Feline Grimace Scale score of 4 out of 10 mean?

For each visible, assessable feature, 0 means the scored change is absent, 1 means it is uncertain or moderately present, and 2 means it is clearly present. When all five features are scored, the total runs from 0 to 10.

A total of 4/10 or higher is a reason to contact your veterinarian about possible pain. The official owner guidance uses that threshold. It is a prompt for professional assessment, not an instruction to give medication or proof of a particular disease.

Research papers may express the result as a ratio. With all five features scored, 4/10 equals 0.4/1. The original study's intervention threshold was above 0.39/1. Those formats describe the same practical boundary for a complete, whole-number score.

There is no safe rule that says 0–3 means everything is fine. If your cat is behaving differently, contact your veterinarian even with a low result. If they appear stable and have no urgent signs, the official FAQ suggests reassessing a concerning low score after 15–20 minutes. Rechecking should never postpone needed care.

What would a score look like in an everyday example?

Here is a fictional arithmetic example, not a way to diagnose the cat in our illustration: ears 1, eyes 1, muzzle 1, whiskers 0, and head position 1. That adds up to 4/10. You would report the observations and ask your veterinarian what to do next.

The useful message is more specific than “the internet says my cat has a four.” It might be: “She is awake, her head is lower than usual, her eyes stay partly closed, and she hasn't come for breakfast.” Those details help put the score in context.

  • Do not turn an unseen feature into 0. If you cannot assess all five, tell the clinic. Do not apply a complete-score cutoff to an improvised total.
  • Do not average away other warning signs. Breathing trouble or inability to urinate outweighs an apparently relaxed face.
  • Do not keep rescoring until you get a number you prefer. A concern worth calling about does not need a perfect calculation.

Could sleep, stress, face shape, or medication affect what you see?

Yes—clinical context matters. A sleepy cat's narrowed eyes are an obvious reason not to score during sleep. A startled cat may also change ear position. The FGS is a pain-assessment tool, not a meter for sadness, fear, or how much a cat likes someone.

Notice whether you are observing a settled cat or a cat reacting to noise, handling, or another pet. Do not assume stress explains away a new change, and do not assume one stressed-looking expression proves pain. Your veterinarian can assess those possibilities together.

Face shape can make features harder to interpret. A study of 28 flat-faced cats undergoing eye surgery found useful responses to pain relief but also limitations, including possible overestimation from images in some cats. That is more nuanced than saying the scale always fails—or works identically—in every breed.

Sedatives, anesthesia, and other drugs also belong in the conversation. After a procedure, follow the clinic's discharge instructions and tell them exactly what was given and when. Do not change a prescribed dose because a facial score went up or down.

Can you use the scale for arthritis or other chronic pain?

Do not use the FGS to clear a cat of chronic pain. Its developers specifically advise against using it to assess chronic conditions such as osteoarthritis. An older cat can have meaningful mobility problems without showing the facial pattern you expected.

For chronic musculoskeletal pain, the AAHA pain guidelines emphasize owner reports of everyday activities and appropriate assessment tools. Notice changes in jumping, stairs, running, and play. A short video of a normal activity can help your veterinarian; do not make a sore cat jump for a demonstration.

For example, a cat who now climbs onto the couch in stages may need a mobility assessment even if their face looks familiar. Our guide to senior cat checkups explains why gradual changes deserve attention.

A cat with a chronic condition can also develop a new acute problem. Do not blame every change on age or an existing diagnosis. Ask the veterinarian how to monitor both the long-term condition and any new signs.

Can an ordinary cat owner use the scale reliably?

You do not need a veterinary degree to learn the observations. A 2021 study found good agreement in overall scores between groups of owners and veterinary personnel scoring cat images. Muzzle and whisker judgments were less consistent.

A larger 2023 caregiver survey received complete responses from 1,262 people in 66 countries. Overall scores were similar to veterinarians' scores, but the work used selected photographs and a convenience sample. It did not show that every owner can diagnose a sick cat at home.

Later research also found the muzzle and whisker features less discriminative than other features. The practical lesson is to use the official training material, admit uncertainty, and bring your observations to a professional. “Validated” describes evidence for a defined use; it does not mean infallible.

Can a photo, the app, or an AI chatbot score your cat for you?

A clear photo or short video may help your veterinarian understand what happened at home. If you can capture one without disturbing your cat or delaying care, include the face and posture in good light. A single frame can catch a blink or an awkward angle, so include context.

Use the resources and app linked from the official FGS website to learn and practice. Learning from reference images is different from treating an automated answer as a veterinary decision.

In a 2025 comparison involving four chatbots and 50 cat images, most tested chatbots showed poor agreement with an expert, with errors that could affect pain-management decisions. That study does not describe every future model, but it is a strong reason not to let a chatbot's reassurance delay a call.

What should you tell the veterinarian?

You do not need a polished report. A few concrete observations are enough to start the conversation:

  • When it started: sudden change, after a procedure, or gradually over days.
  • What you noticed: each facial feature you could assess, your total if complete, and any uncertainty.
  • Daily behavior: food intake, drinking, movement, interaction, and ability to settle.
  • Litter-box output: whether urine is actually being passed, plus changes in stool.
  • Other symptoms: vomiting, breathing changes, injury, or a possible exposure.
  • Medication: name, amount, and time of the last prescribed dose.

Do not let scoring become a detour from the symptom that worried you. A cat who has stopped eating needs attention for that change. Repeated vomiting also has its own warning signs. Neither problem can be sorted out from facial expression alone.

Questions owners ask about cat pain scores

Does a high score tell me where the pain is?

No. Similar facial changes can accompany different painful problems. The score cannot locate the pain, identify a disease, or distinguish one cause of abdominal discomfort from another. Report what else has changed so the veterinarian can investigate.

What if my partner and I give different scores?

Some disagreement is expected, especially with the muzzle and whiskers. Compare your observations with the official examples rather than arguing about a single point. If either person is worried about a new change, call the clinic; you do not need unanimous agreement first.

Should I check my cat every hour?

Ask your veterinarian for a monitoring plan when your cat is ill or recovering. There is no reason to keep interrupting a healthy cat to produce scores. Learn the tool calmly, observe changes when they matter, and seek advice if monitoring is making you unsure what to do.

Can I give a little human pain medicine while I wait?

No—do not give human pain medicine or another pet's medication on your own. The FDA warns that common human pain relievers can harm pets; acetaminophen can be fatal to cats. If something has already been given, contact a veterinarian immediately and provide the product details.

What is the most useful thing I can do with the result?

Use it to communicate sooner and more clearly. A complete score of 4/10 or more warrants a veterinary call; a lower score does not cancel a worrying symptom. Your role is to notice and describe the change. The veterinarian's role is to find the cause and choose a safe plan.

Sources & further reading

Editorial Note: This article reflects information available at the time of publication or its latest documented review. Scientific knowledge, recommendations, and relevant circumstances may change as new information becomes available.

Veterinary Information: This article is for educational purposes and does not replace professional veterinary advice, diagnosis, or treatment. Consult a qualified veterinarian about your animal's health. Seek immediate veterinary assistance if you suspect poisoning or another medical emergency.

Research Context: Scientific findings should be interpreted in light of the methods, sample sizes, and limitations of the cited research. Associations do not necessarily establish causation, and results may not apply to every animal or situation.

Animal Welfare & Safety: Animal behavior, training, handling, housing, and care recommendations should be adapted to the species and individual animal. Prioritize humane methods, appropriate safety precautions, and qualified professional guidance when necessary.

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