June 19, 2025, 3:12 pm | Read time: 9 minutes

What does it mean when your cat stares at you continuously or blinks at you with half-closed eyes? This reveals more about a cat’s feelings and intentions than you might think—you just need to learn how to read them correctly. PETBOOK editor and cat expert Louisa Stoeffler knows how to understand the body language of these animals.

Cats “Speak” with Their Eyes

Unlike dogs, whose body language is usually more familiar to us, cats are still considered difficult to interpret. However, they are no less expressive–their signals are just more subtle. Those who observe them closely will see that cats communicate a lot through body language, including with ears and tail–but they also express quite a bit with their eyes.

The direction of a cat’s gaze primarily reveals what they are focused on. But the type of gaze also plays a role: A fixed stare can mean both curiosity and displeasure. The overall impression is crucial–combined with a tense body, it can be a threat gesture, while with a relaxed, purring animal, it may be an invitation for attention.

When we primarily look at cats’ eyes, the interplay of eyelid position and pupil size is particularly noticeable. This combination conveys messages that can range from very subtle to extremely clear.

Recognizing Emotional Arousal in the Pupil

Whether fear, anger, joy, or excitement–strong emotions in cats can manifest through suddenly dilated, round pupils. This can also be observed with loud noises or unexpected encounters with other cats.

Even when a cat is in a stalking position, ready to attack, the pupils are wide open to keep the prey in sight. Sometimes you can catch them in a funny “pounce.” Large pupils are thus a sign of intense emotional reaction–regardless of whether it is positive or negative.

When the Pupil Takes Up Almost the Entire Eye, Caution Is Advised

Almost black pupils look dramatic and are often a sign of overstimulation or fear. Generally, it is said that the fight-or-flight instinct is activated here, the animal focuses on the situation and has a higher stress or adrenaline level.

A cat experiencing this stress level reacts more strongly to the situation due to the activation of the fight-or-flight instinct. The animal should be gently calmed; otherwise, scratching, biting, or retreating are common further reactions.

My cat Remo shows this when he is particularly scared. Especially at the vet, his iris is usually barely visible. He doesn’t understand that everyone in the practice only wants to help him. His fear is also shown by a tail tucked between his legs and strong body tension. He can only be calmed when I hold him in my arms during the examination.

Trust Is Shown Through Open Lids–Aggression Through Tension

When cats keep their eyes wide open and simultaneously adopt a relaxed body posture, it shows great trust. The eye area is relaxed, the pupil, depending on the light, is slightly slit-shaped, but concave or even somewhat narrower.

If the cat shows a relaxed eye area and the lids are wide open, it is relaxed, somewhat curious, but also feels safe. The pupil changes here only relate to the lighting conditions. However, if the cat squints its lids and the pupil is slit-shaped in normal light, it may be ready to pounce.

A narrow, slit-eyed gaze usually signals strong emotions like fear or aggression. This squinting also serves self-protection: It minimizes the target area for opponent’s claws. Therefore, direct eye contact with a strange cat should be avoided, as it can be perceived as provocation and trigger a defensive reaction. Additionally, one should watch for fixed staring, bristled fur, or hissing sounds.

Contentment Is Shown Through Half-Closed Eyes

When cats look with heavy lids, they often feel comfortable and safe–and are usually about to doze off. Sometimes, in this light twilight state, they don’t fully close their eyes. The reasons for this behavior are explained in this article: Why Cats Sometimes Sleep with Their Eyes Open.

Incidentally, slit-shaped pupils are an adaptation of many cats that hunt at dusk–others, like lions or the Manul, do not have this feature. Slit-shaped pupils can open wider, allowing the animals to see well in poor lighting conditions. In too bright light, they can narrow the pupils to reduce light intake. They can even glow in the dark.

Fixed Gaze–Once a Threat Gesture, Now Adapted to Humans

A fixed or demanding gaze is particularly interesting in cats. Because among their peers, it is considered good manners not to stare. Cats perceive this among themselves as a threat and actually look away when they don’t want to provoke.

However, when communicating with their owners, there can be many other reasons for this. For example, they want to invite us to play, express their interest, ask for food, and much more, which I explain in more detail in this article: 4 Reasons Why Cats Stare at Humans.

Science has also dealt with human-animal communication through eye contact. A research team from Azabu University in Japan presented a fascinating study on this in the journal “Frontiers in Psychology” in 2020. In it, the researchers analyze that the gaze not only serves communication but can also foster emotional bonds between animals and humans. It was compared how dogs and cats, as pack animals and solitary hunters, behave quite similarly in contact with humans.

It was shown that both dogs and cats use gaze behavior to communicate with humans. In neutral situations, cats continue to avoid direct gazes. However, in feeding contexts, they prefer people who look at them and say their name. They follow human gaze directions and associate them with food sources. In certain situations, they show clear bonding patterns–for example, when they consider their human’s emotional expression when assessing an unknown object for danger. The fixed gaze can thus be an exchange of affection–and also strengthens the bond. ¹

How Cats “Hug” with Their Eyes

This feature of feline communication has also been scientifically studied. Because with a slow, accentuated blink (Slow Blink), one tells the cat more than: “I am not dangerous.” Instead, slow blinking in cats is the ultimate sign of love. Because a cat doesn’t actually close its eyes unless it feels full trust and wants to communicate this.

This has also been experimentally confirmed by a study. Tasmin Humphrey and a research team from the University of Sussex and the University of Portsmouth published this in the journal “Scientific Reports” in 2020. In two experiments, it was tested whether cats not only blink themselves but also respond to the slow blinking of humans.

Especially interesting: Cats not only respond to their owner’s blinking but also actively seek closeness afterward. A slow blink can thus help foster trust and closeness. This brings blinking as a means of communication to the center of the human-cat relationship. ²

Of course, I have also tried slow blinking with Remo. He responds to me as well. You can read more about this study and a guide on how to best approach the “Slow Blink” here: Gain a Cat’s Trust by Blinking.

Recognizing Health Warning Signs in a Cat’s Eyes

Eyes are also an indicator of a cat’s health status. Unequal size or pupils that do not constrict in response to light can indicate a medical cause. Immediate veterinary clarification is then required. A possible cause is anisocoria–a condition of unequal pupil widths. It can be caused by infections, tumors, or injuries and indicate serious diseases like feline leukemia (FELV) or eye cancer.

Squeezed eyes or discharge indicate issues like conjunctivitis or glaucoma. Warning symptoms include red eyes, tearing, swelling, or an inflamed third eyelid. General symptoms of illness such as vomiting or diarrhea may also occur.

However, cats also like to hide when they have health problems. Therefore, here is an explanation of how a healthy cat’s eye functions and when one should be concerned.

More on the topic

Behavior explained 4 reasons why cats stare at people continuously

7 tips How to get cats to like you

Study Shows “If You Blink, I’ll Blink Back!” How Dogs React to Other Dogs

Recognizing Vision Loss–Even Without External Signs

Cats have very good depth perception, which allows them to accurately judge distances, especially when moving or jumping. However, this also means that their optimal focus range is about two to six meters away. A cat sees blurry at close range, but this is not due to nearsightedness; rather, it is an adaptation to their hunting lifestyle. They are specialized in spotting prey from afar and then overwhelming it with quick movements. The animals compensate for this poor close vision primarily through their keen sense of smell.

Even if there are no obvious abnormalities in the eye, a cat can have problems with (depth) vision. Typical behavioral changes such as stumbling, avoiding jumps, or increased hiding indicate this. The veterinarian can determine if and what measures are necessary. Because even with severe vision impairments or complete blindness, a cat can lead a fulfilling life–they often orient themselves surprisingly well through other senses.