Veo Video Watermark Detector

Veo's visible watermark: Moving mark
a separate signal underneath: SynthID

Veo watermark

What this Veo video watermark detector checks

Veo can attach two separate signals to its generated video: a visible mark that shifts position over the course of a clip, and SynthID, an invisible signal embedded in the frames. This app checks the visible mark directly, scanning multiple points rather than trusting a single glance. Confirming SynthID with certainty needs Google's own detector, and this app is upfront about that rather than overstating what it can do.

Upload the clip and our own media workflow scans multiple points across the video for the visible mark, reporting what it finds rather than relying on a single glance at one frame. The result comes back on the same screen once the scan finishes running.

The problem

Why a moving mark isn't a one-glance check

A fixed corner logo is easy: look at that one corner and you have your answer for the whole clip. Veo's mark doesn't sit still, so a check based on one frame can miss it entirely if the mark happened to be positioned elsewhere at that instant in the footage.

SynthID is a separate matter entirely. It isn't something you look for the way you look for the visible mark, since it's a sub-perceptual signal requiring Google's own detector to confirm, with no visual shortcut available to anyone else.

The workflow

How to detect Veo's visible watermark in three steps

Everything below happens inside this app, from upload to result.

1. Upload the original clip: Not a re-share, since re-encoding can shift the mark's visibility across the clip.
2. Let the workflow scan it: Multiple points are checked across the clip, since the mark's position moves and a single frame can miss it.
3. Read the scoped result: The result speaks to the visible mark specifically. It says nothing about SynthID either way.

Why it matters

What getting this wrong actually costs

Assuming a clip is unmarked because one frame looked clean is a mistake with real consequences: publishing generated footage as though it were camera-original, or drawing a moderation conclusion from a single, unrepresentative glance at the clip.

Publishing decisions: Confirming a clip's status before it goes into a public deliverable.
Moderation calls: Reading the visible mark as one signal, not a stand-in for SynthID.
Research and archiving: Understanding which signal a given copy can and can't carry.

The mechanism

Why Veo has one signal you can check and one you can't

The visible mark exists specifically to be seen, which is why scanning a clip can actually confirm or rule it out with reasonable confidence. SynthID exists specifically to not be seen, embedded sub-perceptually in the frame data, which is why no amount of looking at a clip, however carefully, settles the question on its own without Google's own tool involved.

Straight answer

Does checking the visible mark tell me anything about SynthID?

No. They're independent signals. A clip can show the visible mark and still carry SynthID, or show no visible mark at all and still carry SynthID, since the two aren't linked in any way. Only Google's own detector can confirm SynthID with certainty; this app checks the visible mark and states that limit directly rather than implying it does more.

Who uses it

Who uses this app, and when

A few recurring, legitimate reasons someone would actually run this check rather than assume.

Editors and publishers: Confirming whether a clip carries the visible mark before it goes into a public deliverable.
Moderators and fact-checkers: Assessing whether a circulating clip shows signs of Veo generation.
Researchers: Understanding the difference between a signal they can check and one requiring Google's own tool.

FAQ

Everything answered. Everything people ask about the Veo video watermark detector

Does Veo put a watermark on its videos?

Yes, a visible mark that moves position across the clip. Output can also carry SynthID, a separate invisible signal.

Can this app check a Veo video?

Yes. Upload the clip and our media workflow scans it for the visible mark.

Is my file uploaded somewhere?

Yes, to our own media workflow so the check can run. It isn't published or shared.

Is there a cost to use this app?

No. There's no charge to run a check through this app.

Can I check for SynthID the same way as the visible mark?

No. SynthID requires Google's own detector, since there's no visual check that works for a sub-perceptual signal.

Does the absence of the visible mark rule out SynthID?

No. The two signals are independent. A clip can carry SynthID with or without the visible mark present.

Can I detect the mark from a single screenshot?

A screenshot only shows whether the mark was in frame at that exact instant, saying nothing about the rest of the clip.

Does no mark in one frame mean the video is clean?

No. The mark moves, so it can be present elsewhere in the clip even if a specific frame doesn't show it.

Can this app prove a clip came from Veo?

No. Finding the visible mark is a strong signal, not a certificate, and its absence doesn't prove the source was unmarked either.

Does re-encoding remove the detectable mark?

Re-encoding can degrade a visible mark but doesn't reliably remove it entirely on its own.

What's the difference between this app and the remover app?

This app checks for the visible mark. The remover app removes it and clears SynthID through regeneration.

Does it matter which frame I check?

Yes. Because the mark moves, checking only the first frame can miss it, which is why several points are scanned.

Is there a batch mode or an API available?

Not yet. For several clips, the fastest route today is one at a time through this app.

Does this app work on phones?

Yes, the upload and the workflow both work in a mobile browser.

Should I check the original file or a shared copy?

The original file whenever possible, since a shared copy has often already been re-encoded before it reaches you.

Is this app useful for content moderation decisions?

Yes, that's a common case here, assessing whether a circulating clip shows visible signs of Veo generation before acting on it.

Can I be certain a clip has no SynthID if nothing is found?

No. Without Google's own detector, this app cannot confirm or rule out SynthID at all.

Does this app cover Sora's watermark too?

No, this app is scoped specifically to Veo. Sora has its own dedicated detector elsewhere on this network.

Is this app affiliated with Google in any way?

No. This app is independent, not made by, endorsed by, or connected to Google in any capacity.

What video formats does this app accept?

Standard formats like MP4 and MOV, the same ones Veo hands you on download.

Is there a length limit for checking a clip?

Ordinary clips process without any trouble. A very long or high-resolution file simply takes a little longer to finish.

Do I need an account to use this app?

No account is required at all for a standard check run through this app.