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, then 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) | ~2–4 MH/s | ~20–35 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.) For the full ladder, from milliseconds to 68,000 years, see the depth ladder.
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 →
Pricing
Every real block is struck on the same ASIC and lands in the same public vault with a verifiable certificate. What you choose is the depth: every extra zero is sixteen times the work, and the plate wears its metal forever. See the depth ladder for the full math.
The toy miner above is free too, no account at all.
Coming soon
Coming soon
Coming soon
Paid strikes need no account: pay, type your inscription at checkout, and the certificate arrives by email. Blocks are standalone artifacts, not tokens; nothing here is an investment.
The foundry queue
Sign in, write a one-line inscription, and watch the ASIC strike it into a genesis block in real time. Up to 10 per account, free during beta.
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