How to Spot an AI-Generated or Face-Swapped Video: 8 Warning Signs

AI-generated videos — clips where a person's face, voice or entire body is synthetically generated or swapped — have moved from novelty to genuine threat. They're used for fraud (fake executives authorizing wire transfers), non-consensual imagery, political disinformation and scams. Here are eight warning signs, roughly in order of how often they still appear, followed by an honest note on their limits.

What a synthetic video actually is

"Synthetic video" covers several techniques: face swaps, face reenactment (puppeteering one person's expressions onto another), fully synthetic AI avatars, and AI voice cloning. Each leaves slightly different artifacts, so it helps to watch and listen for a range of clues rather than one silver bullet.

1. Unnatural blinking and eye movement

Early synthetic videos barely blinked; modern ones over- or under-correct. Watch for eyes that don't blink for a long stretch, blink in unison too mechanically, or gaze in a direction that doesn't track the conversation.

2. The edges of the face

Face-swap models have to blend a synthetic face onto a real head. The seam — hairline, jaw, ears, chin — is where they fail. Look for flickering, blurring or a faint outline around the face, especially when the person turns or a hand passes in front.

3. Lip-sync that's slightly off

Audio and mouth movement rarely line up perfectly in a synthetic video. Watch the mouth on plosive sounds (p, b, m) and wide vowels. If the lips look "dubbed," treat the clip with suspicion.

4. Teeth, tongue and the inside of the mouth

Fine mouth interior detail is hard to synthesize. Teeth may appear as a white smear without individual definition, and the tongue can look absent or malformed during speech.

5. Lighting and skin tone that don't match

A swapped face is often lit differently from the neck, hair and background around it. Look for a face that's a different color temperature, or highlights and shadows on the face that don't agree with the rest of the scene.

6. The head-and-neck boundary

Where the synthesized face meets the real neck, you'll sometimes see a mismatch in skin texture, a hard line, or the head appearing to "float" a little relative to the body during motion.

7. Audio artifacts

Cloned voices can sound flat, have odd cadence, mispronounce names, or lack natural breaths and room tone. A robotic, too-clean voice — or one with strange metallic reverb — is a warning sign on its own.

8. Temporal flicker

Play the clip frame by frame if you can. Synthetic videos often shimmer or flicker between frames — details that pop in and out, textures that crawl — because each frame is generated with slight inconsistencies the eye smooths over at full speed.

Why your eyes aren't enough anymore

The best 2026 synthetic videos exhibit none of these tells at normal playback speed, and compression on social platforms hides the subtle ones. Trained detectors analyze a video frame by frame for statistical and temporal artifacts invisible to humans, which is why serious verification combines automated detection across many sampled frames with a metadata check — and human review when the stakes are high. If you're evaluating a still instead, see how to tell if an image is AI-generated.

Frequently asked questions

Can synthetic videos be detected reliably? Detection is an arms race. A good multi-model detector catches the large majority of synthetic videos, but no tool is perfect. Combine automated analysis with context: does the source, timing and claim make sense?

Is a low-quality, blurry video more likely to be fake? Not necessarily, but scammers often add compression or "shot on a phone" noise precisely to hide artifacts. Low quality should raise, not lower, your guard.

What should I do if I suspect a synthetic video? Don't act on it or share it. Verify through a second channel, and run it through a detector that samples multiple frames. See our detector comparison.