An alternative to ProofStamper
By BlockchainSignLast updated
ProofStamper is the closest competitor to our core claim, and we would rather say so than bury it. It hashes your file locally, sends only the fingerprint, returns an RFC 3161 timestamp certificate, and the base service is free with no account. If that is all you need, take it — this page explains the cases where the difference matters.
What ProofStamper does
You pick a file, it is hashed in your browser, and the hash is sent to a timestamping authority — FreeTSA — which returns a signed RFC 3161 token. The file itself never leaves your device. There is no registration for the free tier, and it takes seconds.
RFC 3161 is the established internet standard for trusted timestamping. It has been in use for decades, courts and technical experts recognise it, and openssl can verify a token with no proprietary tooling. It is a genuinely good standard and we are not going to argue otherwise.
They also publish comparison content in this category that ranks well, which is more than most of our competitors manage.
Where we actually differ
Not on privacy. Both of us hash locally and transmit only the fingerprint, and both of us are right to. The difference is what the proof rests on.
An RFC 3161 token rests on a certificate authority's signature. It is valid because a trusted third party signed it, and it stays verifiable as long as that authority's certificate chain remains available and trusted. That is the model, and it is a sound one — with a specific failure mode: authorities shut down, certificates expire, and chains of trust need maintaining. WIPO's own timestamping service closed in 2022.
A blockchain timestamp rests on a public ledger. It is valid because the transaction is in a chain that no one controls and everyone can read. Nothing needs to keep signing anything, and there is no certificate to expire.
| ProofStamper | BlockchainSign | |
|---|---|---|
| Standard | RFC 3161, via FreeTSA | Ethereum transaction |
| Trust rests on | A timestamping authority's signature | A public, append-only ledger |
| File uploaded | No — hashed locally | No — hashed in your browser |
| Cost | Free tier (watermarked), paid tiers above | $3.00–$9.99 per certificate, no subscription |
| Verify with | openssl, or their tooling | Any block explorer, by eye |
| Readable by a non-technical person | Needs a tool | "View as UTF-8" on Etherscan |
| Long-term dependency | The TSA's certificate chain | None |
| eIDAS qualified | No, and they say so | No, and we say so |
Which failure mode do you care about
This is the whole decision, and it is genuinely arguable.
If you trust institutional continuity, RFC 3161 is more established, more standardised, and better understood by technical experts and courts. It is free here. Take it.
If you would rather not depend on any institution, a blockchain record has no chain of trust to maintain. Our certificate points at one Ethereum transaction containing your payload hash as readable text. It verifies with a block explorer and nothing else — not our software, not our company, not a certificate authority.
Both are defensible. Anyone telling you one is simply correct is selling something.
Credit where it is due
ProofStamper states plainly that its output is not a qualified electronic signature under eIDAS. That kind of accuracy is rare in this category and it is the right way to do it. We say the same about ours, on the Bernstein comparison and anywhere else it comes up.
Using both
For something that genuinely matters, doing both costs almost nothing and gives you two independent records under two different trust models. If one model has a bad decade, the other is untouched. We would not have suggested this if the free tier did not make it nearly costless.
Choose ProofStamper if
- Free matters, and the free tier's terms suit you.
- You want an RFC 3161 token specifically, because someone asked for one.
- You are comfortable verifying with openssl or explaining the standard.
Choose us if
- You want a proof with no certificate chain to keep alive.
- You want a non-technical person to verify it by reading a public transaction.
- You want a certificate document to hand over, not a token file to explain.
- You want the record on a ledger no company operates.