Mina's feature of only 22KB is simply its biggest 'trump card'. This is thanks to its revolutionary core technology—zero-knowledge proofs (zk-SNARKs), which compress the entire state of the blockchain into a small 'fingerprint'.
You can think of traditional blockchains (like Bitcoin) as follows: every new person joining the network must download and verify the entire ledger from start to finish (hundreds of GB) to confirm the current state of 'who has how much money'. It's like having to recalculate every meal and every workout from childhood to now just to know a person's latest weight, which is very cumbersome.
Mina's approach is completely different; it uses a technology called recursive zero-knowledge proofs. You can think of it as:
The state of the entire network (account balances, smart contracts, etc.) is continuously compressed and ultimately becomes a constant size 'cryptographic fingerprint' — approximately 22KB of zero-knowledge proof.
This 'fingerprint' is officially called 'zk-SNARK'. Anyone who validates this small proof can be 100% sure that the entire blockchain history is correct without the need to download any historical data. It's like not needing to review all the details of a person's life; you just need to glance at their latest, authoritative cryptographic health report (proof) to fully trust their current health status. This completely overturns the traditional model of ever-expanding blockchain data.
How can it achieve 22KB?
In Mina, when a new block is generated, miners create a proof that not only verifies the legality of the current transaction but also 'wraps' the proof of the entire chain's state prior to that. This process is like 'Russian nesting dolls', but the size remains unchanged. No matter how long the chain is, what needs to be verified and passed on is always this one latest proof that contains everything.
On Mina, every user is essentially a full node. You only need to sync that 22KB proof with your phone to achieve the same security and validation capability as a node that stores the complete historical data. This truly realizes decentralization because the barrier to entry is very low.
This also makes developing applications on Mina (they call them 'zkApps') really cool. Applications can directly utilize on-chain data and protect user privacy through zero-knowledge proofs (for example, proving you are over 18 without revealing your exact birthday).
This design brings significant advantages but also has its specific operating methods:
Advantages: Very low barrier to entry (everyone can run a node), theoretically more decentralized, and provides a natural environment for privacy-protecting applications.
It is important to note that 22KB refers to that final state proof, not the total data transmitted over the network. The entire historical data of the network ('detailed bill') is still maintained and stored by professional block producers and SNARK workers, among others. Ordinary users only 'trust the result' through validating the proof without needing to store everything themselves.
To put it simply: Mina doesn't give you the entire (Encyclopedia Britannica) but continuously provides you with this unforgeable page of the 'latest summary' of that great work. By validating this page summary, you can fully trust that all the contents of the book are correct and coherent.
In summary, Mina's 22KB is not a simple compression trick, but a paradigm shift achieved through recursive zero-knowledge proofs at the cryptographic level. It reduces the cost of validating the blockchain from requiring massive storage and computation to a level that is almost negligible.
