How Mina keeps a blockchain under 22KB
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This is the first piece in a deep dive series on Mina Protocol. The original version of this article is published on Medium — head there for the full piece. The rest of the series, starting with recursive zk-SNARKs, continues here on the blog.
How does Mina keep its blockchain so small?
Instead of storing the full chain, a Mina node holds a constant-sized cryptographic proof — historically described as 22KB, though Mina's own updated technical breakdown puts the core figure closer to 11KB, depending on what a given node needs to do with it (a light client verifying state has different requirements than a block producer).
That number stays the same size whether the network is a day old or ten years old.
What's the problem with normal blockchains?
One characteristic of blockchain technology is decentralization: the network runs on independent nodes rather than a single central authority. Normally, that means every node has to store and verify the entire transaction history to trust the current state — and that history only grows.
How does Mina solve this?
Mina takes a different approach. It uses recursive composition of zk-SNARKs to represent its blockchain in a constant, succinct form. Instead of storing the full chain, a node holds a constant-sized proof that stands in for the validity of that entire history.
The next article in this series explains the mechanism that makes that possible: recursive zk-SNARKs.
What does the 22KB number actually mean?
- It's not the blockchain data itself — it's a cryptographic proof that the blockchain is valid
- It stays constant — whether the chain has 1,000 blocks or 1,000,000 blocks
- It varies by node type — light clients need less (~11KB), block producers need more
- It's a proof, not a copy — verifying it is equivalent to having verified the entire history
Why does this matter?
- Lower hardware requirements — anyone can run a node on modest hardware
- True decentralization — no need for trusted third parties or archive nodes
- Fast sync — new nodes sync in seconds, not days
- Mobile-friendly — light clients can run on phones
What's next?
Continue to Article 2: Recursive zk-SNARKs for the mechanism that makes this possible.