Find the box “Verify this article”
Open the article. Below the article, near the foot of the page, there is a box headed Verify this article. Every article, brief, Learning Hub dive and Field Guide page has one.
Le Coin / Verify
On-Chain Verification
Check any Le Coin article on Bitcoin
Every article we publish gets a fingerprint stamped into the Bitcoin blockchain. In four steps, and without trusting us, you can confirm that the text of an article is the text we published, and see the Bitcoin block that recorded it.
ABOUT 3 MINUTES · FREE · NO ACCOUNT
You need a web browser. All times on Le Coin are Eastern Time (ET).
Download both files
In that box, click Article file (.html) and Proof file (.ots). The article file is the exact text we stamped; its name ends in -stamped.html. The proof file is the Bitcoin proof for it; its name ends in .ots.
Drop them on opentimestamps.org
Go to opentimestamps.org. First drop the proof file (.ots) into the box that says “Drop here a file to stamp OR an .ots proof file to verify”. A second box appears, “Drop here the stamped file”: drop the article file (.html) there. You can also click each box to choose the file.
Drop the proof file first. If you drop the article file first, the site makes a new stamp of it instead of checking ours.
Read the result
Success is a message headed SUCCESS! that reads “Bitcoin block N attests existence as of DATE”. N is the block number shown in the article’s box. The date, and the time-zone code after it, come from your computer’s settings, so the date can differ from the ET date by a day.
Got WARNING! or FAILURE! instead?
A message headed WARNING! that says “The Bitcoin transaction is unconfirmed” means the proof is not in a Bitcoin block yet. That takes a few hours after publication: download the proof file again later. A message headed FAILURE! means the check did not pass. Reload opentimestamps.org and drop the two files again (the site sometimes fails to load part of itself); if it still says FAILURE!, the article file does not match the proof. We never change articles quietly: every change has a new version, listed in Corrections, with its own proof.
example result (computer set to Eastern Time)
Bitcoin block 971769 attests existence as of 2026-10-16
Mined Oct. 16, 2026, 5:55 p.m. ET · See the block on mempool.space
Bitcoin block 971769 attests existence as of 2026-10-16
Mined Oct. 16, 2026, 5:55 p.m. ET · See the block on mempool.space
What this proves, and what it doesn’t
A matching proof shows that this exact text existed, unchanged, at the time of that Bitcoin block. It does not show that the facts in the article are right: that is the job of our sourcing, fact-checking and Corrections. Think of it as a sealed, dated envelope, not a stamp of truth.
- ✓The text existed at that time
- ✓It has not changed since that block
- ✕The facts are correct
- ✕Who wrote it
Questions
Why Bitcoin?
Bitcoin is the oldest and most widely copied public blockchain. Once a fingerprint is in a Bitcoin block, nobody, including Le Coin, can change or back-date it.
Does it cost readers anything?
No. The files are free downloads, and checking them on opentimestamps.org and mempool.space is free. You don’t need an account, a wallet or any coins.
What if the proof says “pending”?
A new stamp takes a few hours to reach a Bitcoin block. Download the proof file again later from the article’s Verify box; once it is confirmed, the box shows the block number and opentimestamps.org shows the block and date.
Can I check it without opentimestamps.org?
Yes. The article file’s SHA-256 equals the page hash on the article’s Proof page, and the free OpenTimestamps client (ots verify) checks the proof file against Bitcoin.
Do I have to do this?
No. It is there so anyone can check our work without having to trust us.