OpenTimestamps and TimeBinder both prove that a file existed by a point in time by anchoring its fingerprint in the Bitcoin blockchain. Both calculate the fingerprint without uploading your file. They are built for different people. Here is an honest comparison.
| OpenTimestamps | TimeBinder | |
|---|---|---|
| Cost | Free (public calendar servers run on donations) | Free plan: 1 Pooled TimeBind a month. Paid plans from US$20 a month; see pricing |
| Blockchain | Bitcoin | Bitcoin |
| Your files uploaded? | No, hashed locally | No, hashed in your browser |
| What you keep | An .ots proof file for each file | A Proof of Time Certificate (PDF with QR code and transaction ID), plus the record in your account |
| Timing | Pending until the calendar’s next Bitcoin transaction is confirmed; the proof is then upgraded | ASAP: your own transaction, broadcast straight away. Pooled: usually recorded within about 24–36 hours |
| Verifying | OpenTimestamps tools; strongest when checked against your own Bitcoin node | Re-check a file in the browser; ASAP TimeBinds can also be checked directly on the blockchain without TimeBinder |
| Sharing proof | Send the original file and the .ots file | Share the certificate and choose who can verify (public or named email addresses) |
| Best for | Developers and technical users | Professionals, creators and businesses who want a readable certificate and a simple workflow |
Choose OpenTimestamps if
- You are comfortable with command-line tools or the open-source web stamper
- You will keep each .ots proof file safe alongside the original
- You want a free option and do not need a certificate for others to read
Choose TimeBinder if
- You need a certificate that clients, lawyers or insurers can follow
- You want to timestamp up to 10 files together, with a reference and details
- You want ASAP TimeBinds in your own Bitcoin transaction, or the low cost of Pooled
- You want to control who can verify the record
Both approaches prove timing, not authorship or truth. Neither guarantees a court will admit the evidence. Learn more in how verification works and ASAP vs Pooled. Facts about OpenTimestamps are from opentimestamps.org.
Frequently asked questions
Is OpenTimestamps free?
Yes. OpenTimestamps is an open-source project and its public calendar servers are free to use, supported by donations.
Are TimeBinder and OpenTimestamps both on Bitcoin?
Yes. Both anchor a fingerprint of your file in the Bitcoin blockchain, and both calculate that fingerprint without uploading your file.
Which one is more independent?
An OpenTimestamps proof and a TimeBinder ASAP TimeBind can both be checked without relying on the provider. A Pooled TimeBind is cheaper but is verified through TimeBinder.
Why would I pay for TimeBinder?
For a guided web app, a Proof of Time Certificate that non-technical people can read, control over who can verify, and support. If you are comfortable with command-line tools and managing proof files, OpenTimestamps may be all you need.
Start free: your first Pooled TimeBind each month costs nothing.