Is a free proof of existence as good as a paid one?
Often, yes. The strength of a proof comes from its witnesses and from whether anyone can check it, not from its price. Most paid services fingerprint your file, have one witness record the time (often a single blockchain), and give you a certificate. Free witnesses of the same kind exist: public time stamp authorities, OpenTimestamps on Bitcoin, and public randomness beacons. What a paid service usually adds is convenience: a website, a dashboard, storage. What it can take away is independence: if the proof can only be checked on their site, it lasts only as long as they do. Before paying, ask four questions: does my file leave my computer, how many independent witnesses are there, can anyone check the proof without you, and what happens to my proofs if you close?
What makes a proof strong
Independent witnesses: each one is a party you do not control saying the file existed by a time. Two unrelated witnesses are stronger than one.
Open checking: a proof anyone can verify with standard tools outlives the company that made it. A proof that only one website can read is a promise, not a proof.
Your file staying with you: only a fingerprint needs to leave your computer. Uploading the file itself adds risk and adds nothing to the proof.
Signatures that will last: today's common signatures are planned to be retired between 2030 and 2035, so a proof meant to last should also carry a post quantum signature.
When paying makes sense
Organisations sometimes need things a person does not: proofs issued in the organisation's name, qualified time stamps for a particular legal regime, automatic proofs for whole folders, and support. Those are worth paying for. Simply fixing when a file existed is not something a person should ever have to pay for.
Compare any service on four points
- 01
Does the file leave my computer?
It should not need to. A fingerprint is enough.
- 02
How many independent witnesses?
One is a single point of failure. Two or more, from unrelated parties, is better.
- 03
Can anyone check it without you?
Look for a checker you can run yourself, offline, and an open format.
- 04
What happens if you close?
A good proof keeps working without the company that made it.
Rashnova Proof was built to answer yes to all four, free: the file never leaves your computer, four independent witnesses fix the time (drand, two time stamp authorities and Bitcoin), every proof is signed twice, once with post quantum cryptography, and each one carries its own checker that works in any browser, offline, without us. For organisations that need proofs in their own name, Rashnova for Organisations adds that on top.