Can you tell whether a picture was made by AI just by looking at it?

Not by looking. Some tools claim they can; this one does not try. It reads only the records left inside the file — the name of the drawing software, or the signature a generative AI writes. If a record is there, it can say there is a record of AI. If there is no record, it says nothing (FM Score 50 means undetermined).

I want to know whether the art I commissioned was drawn by hand

Ask the artist for the original file they saved, and drop that file here. Originals often still carry the name of the drawing software used. The file can tell you things the finished picture alone cannot.

Which file format should I ask for?

Ask for a PNG original. Through the same route (pixiv), 66.3% of PNGs still carried a record, against 0.0% of JPEGs. JPEG re-encoding throws the record away with it. Simply asking for "the PNG original" keeps the option to check later.

Can I check an image taken from social media?

Almost never. We read 49,649 illustrations in circulation and found that only 0.1% of images that came through X still carried an origin record. Social platforms re-encode what you upload, and the record is dropped in the process. Ask for the original, not the posted image.

This tool does not call hand-drawn work AI. It only speaks up when it can say there is a record of AI; with no record it simply says undetermined. It does not grade the work, and it does not weigh the artist's reputation. The only thing you ask of them is the original file — the rest is you dropping in the file you received.

Does the file I drop in stay anywhere?

The image itself is never sent. It is read inside your browser, and what reaches the server is the file hash and the records read from the file (the drawing software name and so on). The file name is not recorded either. A proof page can only be opened by someone who knows the proof number.

How do I read the FM Score?

50 is the line. 50 means "no evidence either way" — it does not mean AI. The further above 50, the thinner the AI involvement; above 80 it is thin indeed. This tool only looks at the traces left in that one image. It does not weigh the author's reputation or identity. Always check the work with your own eyes as well.

I am the artist. I do not want to be accused of using AI

Drop your original here, get the score and the certificate, and attach the proof page URL to your post or your quote. Anyone can open that URL and confirm it matches the same file. The certificate carries a QR code, so it can be checked from paper too.

How to use

For people who commission illustrations: four-panel comics showing when to use Fudemark.

These comics were made with generative AI to explain how to use the tool. They are not hand-drawn works.

Check a delivered illustration from the file itself

Can you tell whether a picture was made by AI just by looking at it?: Not by looking. Some tools claim they can; this one does not try. It reads only the records left inside the file — the name of the drawing software, or the signature a generative AI writes. If a record is there, it can say there is a record of AI. If there is no record, it says nothing (FM Score 50 means undetermined).
I want to know whether the art I commissioned was drawn by hand: Ask the artist for the original file they saved, and drop that file here. Originals often still carry the name of the drawing software used. The file can tell you things the finished picture alone cannot.
Which file format should I ask for?: Ask for a PNG original. Through the same route (pixiv), 66.3% of PNGs still carried a record, against 0.0% of JPEGs. JPEG re-encoding throws the record away with it. Simply asking for "the PNG original" keeps the option to check later.
Can I check an image taken from social media?: Almost never. We read 49,649 illustrations in circulation and found that only 0.1% of images that came through X still carried an origin record. Social platforms re-encode what you upload, and the record is dropped in the process. Ask for the original, not the posted image.
Is it rude to check?: This tool does not call hand-drawn work AI. It only speaks up when it can say there is a record of AI; with no record it simply says undetermined. It does not grade the work, and it does not weigh the artist's reputation. The only thing you ask of them is the original file — the rest is you dropping in the file you received.
Does the file I drop in stay anywhere?: The image itself is never sent. It is read inside your browser, and what reaches the server is the file hash and the records read from the file (the drawing software name and so on). The file name is not recorded either. A proof page can only be opened by someone who knows the proof number.
How do I read the FM Score?: 50 is the line. 50 means "no evidence either way" — it does not mean AI. The further above 50, the thinner the AI involvement; above 80 it is thin indeed. This tool only looks at the traces left in that one image. It does not weigh the author's reputation or identity. Always check the work with your own eyes as well.
I am the artist. I do not want to be accused of using AI: Drop your original here, get the score and the certificate, and attach the proof page URL to your post or your quote. Anyone can open that URL and confirm it matches the same file. The certificate carries a QR code, so it can be checked from paper too.

Where the numbers come from: we read 49,649 illustrations posted from 2026 onward (an absent record is not evidence of AI).

See the method and the full tables →

If you commissioned the art1. When it is delivered

VTuberMy character art has arrived!
VTuberThey said it was hand-drawn, but I cannot tell by looking…
VTuberLet me drop in the file I received, as it is
VTuberIt still carries a CLIP STUDIO PAINT record. FM Score 65!

Use the delivered file — the one exported by the drawing software.

Before you commission2. You cannot check beforehand

VTuberLet me check their published work before I ask them
VTuber…50. Undetermined?
NoteImages posted to social media are rebuilt, so the records are gone
VTuberThen I will ask for the PNG original at delivery

Of 814 images taken from X, not one still carried a record.

If you hesitate to check3. Checking is not an accusation

VTuberI want to check, but it feels like I am doubting them…
NoteThe FM Score does not call hand-drawn work AI
NoteAcross 590,000 images, it never once called human work AI
VTuberThen I can check without worrying

It only speaks up when it can say there is a record of AI.

For when someone asks later4. You can still say this is what was delivered

SomeoneIsn't that character art AI?
VTuberI issued a proof when it was delivered
Proof pageIssued at / hash of this file / FM Score
VTuberWe can compare it against the file right now

A proof carries the time and the file hash. The time cannot be made up afterwards.

How to use it5. There is only one step

VTuberChoose the delivered file (not one re-saved from social media)
ScreenYou get the FM Score and the certificate
NoteIf it says there is a record of AI, that is close to certain
Note"Undetermined" does not mean anything is wrong

Art drawn in phone apps always comes out undetermined. That says nothing about the work.

If you are delivering the art6. You can send it with the work

ArtistFinished. Let me drop in the original I exported, as it is
ScreenYou get the certificate (you can save it as a PDF)
ArtistI will send this along with the original
VTuberI can check on the spot that it is the same file

It is not proof that no AI was involved. It records what the file carried.

When you get 50

50 means "we cannot tell". It is neither a clean bill nor an accusation. Most of the time nothing could be measured — but unsigned AI also lands here.

You used an image re-saved from social media: Nothing was measured. Try again with the delivered file.; Of 814 images taken from X, not one still carried a record.
It was drawn in a phone app: The artist did nothing wrong. There is simply nothing to read.; ibisPaint writes no software name and no timestamp, in PNG or in PSD (checked on a device).
It was delivered as JPEG: JPEG does not erase records. Re-encoding along the way does.; 531 of 37,396 JPEGs still carried a record. Via pixiv: 0.0%. Via DeviantArt: 37.6%.
It was lost on export: The same artist and the same drawing can keep or lose the record, depending on how it was exported.; Of 2,475 images by one artist, 1,243 carried no record at all.
It was AI without a signature: This one remains. 50 does not mean "not AI".; About one in ten undetermined files was AI-generated (69.3% of civitai and 75-83% of booru AI tags land here).

In short

1When you commission, ask for the PNG original at delivery
2Choose the delivered original file (not an image re-saved from social media)
3Check the FM Score and certificate, and keep the proof page URL so you can compare the file later