Strike a Block
Every blockchain begins with a single block, and every genesis block carries an inscription that can never be edited out. Satoshi wrote a newspaper headline. This page lets you write yours — and mine it, for real, right here in your browser.
The original
Billions may be needed as lending squeeze tightens. The Chancellor will decide within weeks whether to pump billions more into the economy as evidence mounts that the £37 billion part-nationalisation has failed to keep credit flowing.
On 3 January 2009, someone using the name Satoshi Nakamoto mined block 0 — the genesis block — and inscribed that day's Times headline into it. Every one of the billion-plus Bitcoin transactions since traces its ancestry to this one block.
The block below is the real thing — its actual hash, nonce, and inscription, exactly as they sit at the root of the chain today.
Plain terms
A genesis block is simpler than it sounds. It's made of three things you already understand — or take the 5-minute interactive lesson and learn it by breaking one.
A blockchain is a book of records where each page references the page
before it. The genesis block is page one — the only page with nothing
before it. Its “previous page” field is just zeros:
000…000. Every chain, including Bitcoin, has exactly one.
The miner of a block gets to include a short message. Change a single letter of it, and the block's fingerprint — its hash — changes completely, breaking every page that follows. That's why Satoshi's headline can never be quietly edited. Inscriptions are permanent.
Mining means retrying the block with different “nonce” numbers until its hash starts with enough zeros. Finding one takes billions of tries; checking one takes an instant. The zeros at the front of a block hash are the receipt for the work.
Then & now
A block at Bitcoin's original difficulty needs about 4.3 billion hash attempts on average. Here's what that costs, by machine:
| Machine | Hash rate | One genesis-difficulty block, on average |
|---|---|---|
| 2009 desktop CPU (what Satoshi used) | ~6 MH/s | ~12 minutes of steady hashing |
| Your browser, this page (JavaScript) | ~0.5 MH/s | ~2½ hours |
| One USB stick miner, 2026 (BM1397 ASIC, 672 cores) | ~200 GH/s | 21 milliseconds — about 47 blocks per second |
The demo below uses a friendlier target — a hash starting with four zeros, about 65,000 attempts — so your browser can strike a block in around a second. Same mechanism, smaller mountain. (Curious about block 0 itself? The six-day gap between it and block 1 remains one of Bitcoin's small mysteries.)
Your turn
Type an inscription. Your browser will hash it with a timestamp and a counting nonce — double SHA-256, the same algorithm as Bitcoin — until the hash starts with the zeros you asked for. Nothing leaves this page.
The vault
Blocks below were mined not by a browser but by a GekkoScience Compac F — a thumb-sized ASIC with 672 hash cores — at Bitcoin's original genesis difficulty. Full 32-zero-bit proof of work, the same bar Satoshi's block cleared.
The vault is public and anonymous — inscriptions appear without any information about who requested them. The six most recent strikes show here; browse the complete archive →
Coming soon
Browser blocks are toys — real ones clear the same difficulty as Bitcoin's block 0 and come with the full header, coinbase transaction, and proof you can verify with one line of code. Sign in with Google, leave your inscription, and the foundry mines it within minutes.
Sign-in is only used to queue your request. The vault never shows who asked.
You type your inscription at checkout. No account, no sign-in — the foundry strikes it privately and emails your certificate.
The queue
One line, up to 90 characters. The foundry strikes it at Bitcoin's original difficulty and it appears in the vault above — anonymously, usually within minutes.
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