Every cell image, signed at the source.

CellProof takes a fingerprint of each microscope image and signs it with your lab's key. Change one pixel, or slip in a generated cell, and the proof no longer matches. Poisoned images get caught before they reach the AI.

Real blood smear with a neutrophil, as captured — Plate A · as captured · signed Checking
Verifying signature…

Same blood smear with one pixel changed — Plate B · same image · 1 pixel changed Checking
Verifying signature…

Real stained blood smear, image BloodImage_00000 from the BCCD Dataset (MIT license). Red blood cells around one neutrophil. Signed live in your browser with a throwaway "Demo Lab" key.

Walkthrough

How it works

Follow one real blood smear from the microscope to the AI training set. Then try to sneak something past CellProof.

White blood cellRed blood cell

Step 1

Sign images

Sign images right after capture. Each signature records the image fingerprint (SHA-256), who signed it and when, using ECDSA P-256, the same signature family the C2PA standard uses.

Signer

Sign with the Hasky Labs key (server-side; only the fingerprint is sent, never the image)

Key IDGenerating…

Key created–

Drop microscope images to sign or tap to choose files · PNG, JPEG, TIFF · only the fingerprint leaves this browser, never the image

No microscope images? Try a real sample:

Signed images appear here.

Step 2

Verify images

Drop any images, for example a training set, to check them against the ledger. Green means signed and unchanged. Red means changed since signing. Amber means no signature was found. Every image also gets a synthetic check: a small model, trained on 31,000 real blood cells, looks for the frequency fingerprints that upscalers and generators leave behind. Need something you can hand to an auditor? Any verified image can be turned into a signed proof: a printable certificate with the fingerprint signed by the Hasky Labs key, 199 kr.

Demo onlyResults compare against signatures made in this browser. "Unsigned" means no CellProof signature was found, not that the image is fake. The synthetic check (detector v0) catches resampled and blended images well but misses spliced ones; it is a screening hint, not proof. This is not a medical result.

Drop images to verify or tap to choose files

No microscope images? Try a real sample:

Tip: sign a sample above, then verify the same one here. It turns green. Save a sample with this link, edit it in any photo app, and verify it again. It turns red.

Verification results appear here.

Step 3

Ledger

Every signature this browser knows about. Copy it to share with another lab, or paste one in to check their images.

Image	Fingerprint (SHA-256)	Signer	Signed at

Paste signatures (JSON)

Contact

Build it with us

Work in hematology, digital pathology, lab software or medical AI? Interested in investing in trust and safety for healthcare AI? We'd love to hear from you.

hello@cellproof.io