Google’s SynthID Detector helps users check if images, videos, or audio files are AI-made. The tool scans for invisible watermarks embedded by compatible systems. It supports 11 image, 3 video, and 6 audio formats. While it helps verify suspicious files, it only works if the content carries a detectable SynthID watermark.

What problem does it solve?

A photo arrives with a damage claim. A voice note that sounds like your CEO asks for urgent payment. You suspect AI, but cannot check, so you either trust it or lose a day escalating it.

Finance, HR and legal teams increasingly face the challenge of assessing potentially synthetic media. Google's SynthID Detector offers a first check: upload a file to see whether it carries a SynthID watermark, an invisible marker embedded by compatible AI systems. The technology is designed to help identify AI-generated or AI-edited content, though its coverage depends on whether the file carries a detectable watermark.

What can it do?

Verify before acting: Check a suspicious file in minutes instead of escalating it.

Cover every format: Test 11 image, 3 video, and 6 audio formats, from HEIC to MP3.

Resist typical edits: Google says watermarks are built to survive compression, cropping, and filtering.

Example

A finance manager receives a vendor’s bank-change request with a supporting voice note, and payment is due by evening.

Sign in: Go to synthid.com and sign in.

Upload the file: Choose “Upload file” and select the voice note, for example an M4A or WAV.

Read the result: The site reports “watermark detected” or “watermark not detected.”

Interpret carefully: Detected means it was likely generated or edited by a SynthID-enabled model; not detected rules nothing out.

Gather more evidence: Call the vendor on a known number and escalate to security before paying.

Edge case worth knowing: It cannot tell AI-created from AI-edited media, and rare false triggers can occur.

Where it works, and where it does not

Works: Images, video, and audio from Google, OpenAI, NVIDIA, and Kakao. The site supports JPG, JPEG, PNG, BMP, WEBP, AVIF, HEIC, HEIF, TIFF, TIF, and GIF for images; MP4, MOV, and WEBM for videos; and WAV, MP3, OGG, FLAC, AAC, and M4A for audio.

Does not work: Content from Microsoft, Meta, or any model without SynthID, text, and heavily altered files.

Not yet: Apple support has no announced date.

What makes SynthID Detector special?

Intentional signal: Unlike guess-based detectors, it finds a mark planted at creation, so a positive is strong evidence.

Shared infrastructure: A mark used by many labs becomes a common verification layer, not one company’s feature.

Proof of AI only: It can confirm AI origin, never certify a file is real.

Mint's ‘AI tool of the week’ is excerpted from Leslie D'Monte's weekly TechTalk newsletter. Subscribe to Mint's newsletters to get them directly in your email inbox.