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Free blockchain timestamp options: what “free” gets you
Clicking opens the TimeBinder app. Files are hashed locally on your computer; nothing is uploaded or stored by TimeBinder.
You can timestamp a file on the Bitcoin blockchain without paying. Here are the honest options, how they manage to be free, and when paying for your own transaction makes sense.
Your files never leave your computer. With TimeBinder, each file is hashed locally on your own device. Nothing is uploaded or stored by TimeBinder.
Is there a free blockchain timestamp?
Short answer: yes, you can get a blockchain timestamp for free. OpenTimestamps is a free, open-source service that batches file fingerprints into Bitcoin transactions. You keep a small .ots proof file and can check it yourself with their tools. TimeBinder’s Free plan gives you one Token each month, enough for one Pooled TimeBind with a readable certificate. Pooled TimeBinds are checked through TimeBinder. If you need a record anyone can check without relying on TimeBinder, an ASAP TimeBind (3 Tokens) gets its own Bitcoin transaction.
Whichever you choose, a timestamp shows only that an exact file existed no later than a recorded time. It doesn’t show who made it or that the contents are true.
What is TimeBinder? TimeBinder is a blockchain timestamping service. It shows that a digital file existed no later than a specific time, and that it still matches its fingerprint, by anchoring the file’s SHA-256 fingerprint to the Bitcoin blockchain. Files are hashed in your browser and never uploaded, and each TimeBind comes with a Proof of Time Certificate that can be checked later. It does not prove who created a file or that its contents are true.
How a blockchain timestamp can be free
Each Bitcoin transaction costs a network fee. Free services keep costs down by batching: they combine many file fingerprints into one value (using a structure called a Merkle tree) and record that single value in one transaction. Everyone in the batch shares the cost, and each person gets the path that links their fingerprint to the transaction.
The trade-off is time. A batched timestamp waits for the next batch transaction and its confirmation. The OpenTimestamps client documentation says it takes a few hours for a timestamp to be confirmed; TimeBinder’s Pooled TimeBinds are usually recorded within 24 to 48 hours, and often sooner, depending on Bitcoin network activity.
Option A: OpenTimestamps
OpenTimestamps is free and open source. Its public calendar servers are free to use, need no registration or API key, and rely on donations. You can stamp from the command line (ots stamp my-file) or with the in-browser stamper on its website, which hashes the file in your browser. You get an .ots proof file that you must keep safe next to the original; without it, the timestamp can’t be checked. Verification is strongest against your own Bitcoin node. For a deeper look, see TimeBinder vs OpenTimestamps.
Option B: TimeBinder’s Free plan
The Free plan is $0 and includes 1 Token a month, which covers one Pooled TimeBind of up to 10 files. Your files are hashed on your own device and never uploaded. You get a Proof of Time Certificate, a PDF with a QR code and the Bitcoin transaction ID, which is easier to hand to a client or a lawyer than a proof file. Pooled TimeBinds are verified through TimeBinder. The Free plan’s monthly Token doesn’t carry over if unused. See TimeBinder pricing and Tokens.
Option C: do it yourself
You can put a file’s SHA-256 fingerprint into your own Bitcoin transaction (for example in an OP_RETURN output). You pay the network fee, which varies, and you need a wallet and some technical know-how. You also need to keep clear notes so someone else can follow how to check it later. For background, see how blockchain file verification works.
When paying makes sense
If timing might be disputed later, or the person checking won’t want to rely on TimeBinder, an ASAP TimeBind (3 Tokens) sends your own Bitcoin transaction straight away. It can be checked independently, from the certificate and the public Bitcoin blockchain. See ASAP vs Pooled verification for the details. If you need a timestamp from a trusted timestamp authority instead, compare RFC 3161 vs blockchain timestamps.
Which free blockchain timestamp is right for you?
| OpenTimestamps | TimeBinder Free (Pooled) | TimeBinder ASAP | DIY Bitcoin transaction | |
|---|---|---|---|---|
| Price | Free (donation-funded calendars) | $0: 1 Token a month | 3 Tokens (USD) | Network fee (varies) |
| Interface | Command line or in-browser stamper | Web app and certificate | Web app and certificate | Wallet and technical steps |
| Files uploaded? | No (hashed in your browser or client) | No (hashed on your device) | No (hashed on your device) | No |
| How it’s checked | Independently, with the .ots file | Through TimeBinder | Independently, with the certificate and the Bitcoin blockchain | Independently |
| Time to confirm | A few hours (batched) | Usually 24 to 48 hours, often sooner (batched) | Broadcast straight away; confirmation depends on the network | Depends on the fee you pay |
| What you must keep | The .ots file and the original | The original file (certificate is in your account) | The original file and certificate | The original and your transaction notes |
| Better fit when | You’re technical and want open source | You want a readable record for routine drafts | Timing may be disputed later | You want full control |
OpenTimestamps details are from opentimestamps.org and its client documentation, checked on 30 October 2026.
What any of these timestamps shows, and what it doesn’t
What it shows
- That this exact file existed no later than the time recorded on the Bitcoin blockchain
- That a file shown later still matches its fingerprint: the same file gives the same fingerprint, and any edit gives a different one
- A record kept outside your own systems: an ASAP TimeBind can be checked on the Bitcoin blockchain without relying on TimeBinder, and a Pooled TimeBind is verified through TimeBinder
What it doesn’t show
- Who created, wrote or signed the file
- That the contents are true or accurate
- Whether AI was used to make it
- How a court or other decision-maker will treat it: that depends on the jurisdiction and the rules that apply. It isn’t legal advice
Pooled TimeBinds are verified through TimeBinder. ASAP TimeBinds can also be verified independently, from the certificate and the public Bitcoin blockchain. Checking is always free.
How to timestamp a file with TimeBinder
Three steps. Submitting takes a few minutes; a Pooled TimeBind is usually recorded within 24 to 48 hours, and often sooner, depending on Bitcoin network activity, and ASAP is faster.
Drop your files
Add up to 10 files per TimeBind. Any file type and size works.
draft.docx · design.figHashed on your computer
Your browser works out a unique SHA-256 fingerprint for each file. Nothing is uploaded. The files never leave your device and TimeBinder never stores them.
fingerprint 9f2c…41ab · file stays with youSealed to Bitcoin
The fingerprints are anchored to the Bitcoin blockchain: ASAP (your own transaction, sent straight away) or Pooled (usually recorded within 24 to 48 hours, and often sooner, depending on Bitcoin network activity). You get a Proof of Time Certificate, a PDF with a QR code and the Bitcoin transaction ID.
✓ sealed · certificate ready
Free blockchain timestamps: FAQ
Is there a free blockchain timestamp?
Yes. OpenTimestamps is free and open source, and TimeBinder’s Free plan includes 1 Token a month, enough for one Pooled TimeBind.
What’s the catch with free timestamps?
They are usually batched, so they take hours to confirm. Some depend on you keeping a proof file safe; others are checked through the provider.
Is OpenTimestamps really free?
Yes. Its public calendar servers are free to use and supported by donations. You must keep your .ots file safe alongside the original file.
Can I check a free TimeBind without TimeBinder?
A Pooled TimeBind, including the free monthly one, is checked through TimeBinder. An ASAP TimeBind can be checked independently, from the certificate and the public Bitcoin blockchain.
Does a free timestamp show less than a paid one?
It shows the same thing: that an exact file existed no later than a recorded time. The differences are how it is checked and how fast it confirms.
What does it cost?
The Free plan is $0 and includes 1 Token a month. A Pooled TimeBind costs 1 Token and an ASAP TimeBind costs 3 Tokens; checking is free. Essential is $20 a month for 5 Tokens ($4 per Token, against $5 pay-as-you-go) and Expert is $50 a month for 15 Tokens (about $3.33 per Token). Paid plans replace the Free plan’s monthly Token, so Essential adds 4 Tokens for $20 and Expert adds 14 for $50.
Try a free TimeBind
Here’s what you’ll do next:
- Open the app and sign in with email or Google.
- Add your files. They stay on your computer.
- Seal them and download your Proof of Time certificates.
Start free: your first Pooled TimeBind each month costs nothing. See pricing