How To Tell If Someone Is Lying To You: 34 Signs To Watch For

This one might seem counterintuitive but it’s true. TMI can be a sign of lying. People who are lying want you to believe what they're saying and don't want you to get suspicious, so sometimes they tend to overdo it on the details. "People will give you more details than what is necessary because they have fabricated an intense lie, and they need to tell you all the details of the lie because they've memorized the whole story," Casherie Bright, a mental health counselor, tells Romper. "Sometimes if you come back and clarify or ask advanced questions, they get tripped up."

Of course, completely changing a story from one telling to the next is an obvious sign that someone might not be telling the truth, but even tiny, subtle changes can indicate a lie — for instance, the person saying they did something that doesn’t make logistical sense. According to a 2012 study in Applied Issues in Investigative Interviewing, Eyewitness Memory, and Credibility Assessment, researchers found that inconsistency in stories is the most often cited reason for discrediting others.

You can likely envision someone who is lying putting up an emotional or communicative wall, but the same goes for physical walls, too. “Putting items — hands, crossed arms, elbows — between themselves and the other person are also ways in which liars will sometimes try to ‘barricade,’ themselves, subconsciously,” Dimitriu says. When it comes to the body language of a liar, you can tell something is up if someone is consciously or even subconsciously putting up a wall between you.

While providing far too many details can certainly be a sign of deception, Bright says that saying too little is also a sign that they might be lying to you. In this case, "[s]omeone gives you [very little] information, very briefly answers questions, and seems disinterested or disconnected from you," she says. They don't want to get caught telling lies, but they don't have the details.

Changes in eye contact can also be important to note, though they’re more subtle than other body language queues. "Many times people won't look you directly in their eye when they're lying," Bright says. "Or they will look you in the eye as a staring and power play and then when you meet their gaze they dart their eyes away from you." In a similar vein, blinking faster or slower than normal can also be a sign of lying, as can other abnormal eye behaviors.

A fake smile might be a giveaway that something's not right and watching for a fake smile is a pretty easy way to tell if someone is lying to you. But, do you know how to spot one? A Duchenne smile, aka smiles that are formed by flexing facial muscles that make the skin around the eyes wrinkle, is what most consider a true smile, as it is associated with authentic pleasure. A non-Duchenne smile is formed with no contraction of the muscles around the corner of the eyes — a fake smile, that is. And as it turns out, people naturally view Duchenne smiles in a more positive light, according to a 2016 study published in Cognition & Emotion. So trust your own intuition when it comes to insincere smiles.

It can sometimes be difficult for people who are lying to answer questions — especially super-specific questions — about their lie. A 2009 study published in The American Journal of Forensic Psychiatry found that fabricated stories tend to be lacking in contextual details, but at the same time come with spontaneous rationalizations for the limited details — aka on-the-spot excuses for the lack of specificity. So, if you're asking for more details and they can't seem to remember the cuisine of the restaurant they claimed to eat at or where in town the store is where they said they were shopping, it might be a sign that they're not telling you the truth.

If you ask someone a question and they immediately get defensive and worked up, it might be because they're lying, Dimitiu tells Romper. It's generally not a good sign, and you’re probably not getting the whole truth at the very least. Hostility toward you may stem from the need to self-preserve and prevent you from detecting the lie.

Interestingly enough, if you're talking to someone and it seems like their voice is a higher pitch than usual, it could be that they're lying. In fact, a 2021 study published in Nature Communications found that human voices tend to have a particular sound signature when telling the truth. Not only that — the researchers also found that we have a built-in mechanism in our brains used to detect when someone is telling us a lie based on the change in their voice. Basically, our brains can pick up on truth telling in most other people automatically.

Your pupils dilate (get bigger) when there is an increase in brain activity. According to a 2018 study published in Frontiers in Neural Circuits, changes in pupil diameter are thought to coincide with the activity of neuromodulators, so when your brain is working harder, your pupils will get bigger. Given that, it makes sense that if someone is trying to convince you of a lie, their pupils will dilate. And because pupil control can’t be learned or altered, it’s a helpful indication that someone is being deceptive.

Watching for unnecessary pauses or hesitations can be way to tell if someone is lying, as they’re a way for the person to stall a bit and figure out what to say next. According to a 2011 study published in The American Journal of Forensic Psychiatry and conducted by researchers at UCLA, liars often slow down their speech and take long unnatural pauses in order to monitor the listener's reaction to what they are saying. By doing so, it gives them time to gauge your response and help create their story in real time.

Relatedly, after a liar takes pauses to both monitor your reaction and help think about what they’re going to say next, they might begin to speed up their speech in an abnormal sounding way. The UCLA researchers found that once the person telling the falsehoods had their story straight, they began to spew it out faster, as they thought speaking too slowly for too long would be perceived as suspicious. On the flip side, people telling the truth weren’t bothered at all by speaking slowly. In fact, the study found that truthful people didn’t dramatically alter their speech rate within a single sentence at all.

When you're having a conversation with someone, it might not be all that unusual to incorporate filler words such as “um,” “uh,” and “like” into the discussion where they'd naturally fit. When you're lying, however, it's less likely that you'll use these types of natural speech words, according to a 2010 study published in Applied Psycholinguistics. The study found that instances of “um” occurred less frequently during lying as compared to truth-telling and concluded that words like “um” form an important part of authentic, effortless communication — which tends to be lacking when someone is fibbing.

Some people just naturally twirl their hair, so as with everything else on this list, this sign alone does not mean that someone is lying to you. However, the UCLA study published in the American Journal of Forensic Psychiatry found that people lying are more likely to engage in grooming behaviors, such as playing with their hair or pressing fingers to their lips when asked a sensitive question. So if you’re wondering if someone is lying to you — maybe if you’re a bit suspicious to begin with — keep a close eye out for behaviors like this.

When people tell the truth, their words and sentences tend to flow at a consistent rate natural to that person’s speech style, according to the 2011 UCLA study. However, liars were found to display dramatic fluctuations in their speech rate, including major hesitations, stammers, and the use of fragmented syntax. Particularly if you already know the speech style and general cadence of the person you’re talking to, it can be helpful to notice if their words don’t flow the same as usual when trying to find signs that they’re lying.

Unless the person lying to you is well-versed in body language, if they're facing the door, they're likely trying to get away from the conversation. As Dimitriu explains, “looking towards an exit (such [as] a door)” is a pretty good indication of someone lying, as they don't want to get caught and are either consciously or subconsciously thinking of how to get out of that situation without being found out.

Another sign of deception is the use of lots of unnecessary superlatives and exaggerations where they don't belong. This is one of the most common things HR professionals use to indicate lying in job interviews, as well as on resumes and cover letters. In fact, according to Monster's 2019 State of the Recruiter survey, 85% of recruiters reported finding that candidates exaggerate skills and competencies on their resumes.

Repeating words, phrases, facts, and details can be a stalling tactic. It could also be a sign that they're really trying to convince you — and maybe trying to convince themselves — that the lie they're telling is actually the truth. “Liars also tend to use a lot of detail, and will tend to repeat facts, as if trying to be more assuring,” says Dimitriu.

Usually, when people are being truthful, what they're saying and feeling tend to match. And that certainly goes for feeling fear. People telling the truth likely won’t feel fear, since they have nothing to be afraid of. As found in a 2021 study published in Frontiers in Psychology, when programmed to detect fear, an AI machine achieved above 80% accuracy in sorting liars from truth-tellers, thus indicating that fearful expressions — even if at times fleeting — are good markers for lying.

Someone who is lying to you will tend to be “avoidant of the subject matter,” Dimitriu says. Changing the subject is often something people who are lying want to do, simply because it takes the heat off of them and prevents them from being found out. If you're talking about something else, you can't focus as much on the lie just told to you, and there's less of a chance that you'll immediately figure it out.

If someone responds to your questions with more questions or answers you with non-answers, it’s a good sign that they are lying to you. Evasive phrases such as “Why do you want to know?” or “Do you think I would do that?” as opposed to a straightforward “I didn’t do that” are one clue that someone is being deceptive. In fact, in one 2018 study published in Frontiers in Psychology, evasive answers yielded higher rates of lie detection than story consistency (and the combination of both produced the highest accuracy rates).

Eye contact is a tricky one but if you know a person well, watching their eyes may be a way to tell if someone is lying to you. You might think that averting eye contact is a sign of deception, and sometimes that’s true, but for the most part, when truthful people are asked difficult questions, they tend to look away simply due to the fact that the questions require concentration, according to the UCLA study. What you should look out for, though, is when a person’s eye contact seems unnatural. According to the UCLA research, dishonest people will look away only briefly, if at all, which is opposite to what truth-tellers do. So, if you ask a question that likely requires some thought, but a person doesn’t look away to think, take note.

Another sign of lying? Not speaking in full sentences. The UCLA researchers also found this to be a possible sign of deception. The study found that people lying tend to use sentence fragments more frequently than truthful people. In many cases, people telling falsehoods will begin an answer, back it up, and not complete the sentence.

Most everyone has experienced a situation where they began sweating uncontrollably due to anxiety, stress, or fear, even if for a small reason and their brain was telling them everything was fine. This form of sweating (as opposed to, say, physical sweating from heat and exercise) is regulated by psychological stimuli and specific to body sites with apocrine glands, including the face, palms, armpits, and soles, according to a 2013 study published in Skin Pharmacology and Physiology. When a person is lying, their bodily response might betray their words and demeanor, simply because psychological sweat can be triggered by stress and anxiety.

Another telltale sign that someone is lying to you is when they try to justify everything they say, even when they aren’t asked to do so. According to the UCLA study, although deceptive people tend to not say much overall, they do tend to spontaneously give justification for what they are saying, without being prompted. This is likely due to the fact that they are trying extremely hard to convince you they’re telling the truth, so they have a justification or excuse for just about everything in order to make it sound more plausible. However, if they are justifying one too many things without prompt, it might be because they are overcompensating and lying.

Not using "I" statements is one way to make it seem as though you're not the one lying. It's a way of taking the personal blame away and the focus off yourself. As evidenced in a 2015 study by University of Michigan researchers, when people are deceptive, they distance themselves by using words such as “he” or she,” as opposed to “I” or “we.” Truthful people, on the other hand, are more likely to speak in first person. So, if you notice someone steering away from the use of “I,” it might be an indication of lying.

If they repeat the questions you ask them back to you before actually responding, they might be looking for a way to buy some time in order to concoct an answer, the UCLA researchers found. In the little bit of time it takes for them to parrot the question back to you, they're trying to come up with a passable response that — hopefully — won't invite more questions.

Most people talk with their hands — it’s extremely commonplace. Interestingly, though, the University of Michigan researchers found that when people lie, they often use their hands differently than those telling the truth. In the study, the liars gestured with both hands 40% of the time, compared with 25% of the time among people being truthful. More often, the people telling the truth gestured with just one hand. Perhaps this stems from the idea that liars are more prone to exaggeration, both in their words and their hand movements.

There’s a reason why we have the expression “their face turned as white as a ghost” or “white with terror.” As it turns out, emotions correspond to changes in the central nervous system, so these changes in blood flow are visible as different facial color patterns, according to a 2018 study published in Proceedings of the National Academy of Sciences. When we’re fearful and stressed — such as from telling a lie — blood flow increases to our vital organs as part of our fight-or-flight response, while the blood vessels narrow on the surface of our skin, making our complexion turn pale. And we’re actually pretty good at identifying people’s feelings based on the changing colors of their faces, too — the study found that people had around 75% accuracy based solely on subtle changes in coloring.

If someone is lying to you, you might notice they start to breathe more heavily, which is due to a fight-or-flight reaction. According to the NHS, fight-or-flight reactions make our breathing shallower and more rapid in order to increase oxygen intake, prepping our bodies for action (like bolting out the door). However, when we don’t use this extra oxygen to flee or fight, there is temporarily an imbalance in the amount of oxygen and carbon dioxide in our blood, creating the need for more oxygen, and thus increasing breathing. Since lying can make some people internally nervous and defensive when questioned, their natural fight-or-flight mechanisms can result in an increase in their breathing pace.

People often think that when someone lies, they will tell elaborate, lengthy stories — and this can certainly be true depending on the person. However, the UCLA study found that generally the opposite is true. When questioned, deceptive people were found to want to say as little as possible, and truthful people offered details when challenged. So, if you are just being given bare-bones information when it comes to answers, even as you press for more information, it might be that the person is lying to you.

While you might think that fidgeting indicates someone is lying to you, the opposite is actually more true. In fact, a 2020 study in Frontiers in Psychology indicated that increased cognitive demand — meaning the hard thinking someone does while lying — typically leads to fewer hand and arm movements and inhibits fidgety behavior. Because they are focusing so hard on telling the lie and convincing you, they neglect a lot of otherwise natural, unconscious non-verbal cues. So, if the person you're talking to is eerily still, it could be a sign they're not telling you the truth.

Microexpressions, which flash ever-so-briefly across a person's face, can be hard to spot, but if you do see them, it may indicate that someone is lying to you. According to a 2018 study published in Frontiers in Psychology, microfacial expressions of emotion were found to help in both identifying deception and predicting future deception from those same individuals. So, if you learn how to see them (there are practice tests online), you might be better at spotting a lie as well.

In their study, the UCLA researchers also found that using hands to gesture toward one's self tended to be a sign of deception, whereas those telling the truth tended to gesture outwardly. This may be due in part to the notion that liars tend to be overly defensive and adamant in convincing you that they are not the problem.