In one sentence
Like Solana, Sui chases speed, but in a different way. Solana puts every transaction in one line and then executes in parallel; Sui first asks: will this transaction compete with anyone else for the same thing? If not, it does not need to wait for network-wide ordering and takes a fast path.
It does not use Ethereum’s EVM. Contracts are written in Move, and its wallets, addresses and token standards all differ from Ethereum’s.
Where it came from
In 2019 Meta (then Facebook) announced the stablecoin project Libra, later renamed Diem, and designed the Move language for it. Under regulatory pressure the project was wound up in 2022.
Core members left in 2021 to found Mysten Labs, adapted Move into Sui Move, and launched Sui mainnet on 3 May 2023. Another chain from the Diem team is Aptos.
- 2024: the new Mysticeti consensus went live, shortening confirmation times further.
- May 2025: Cetus, the largest DEX on the chain, was exploited for about $220 million. Sui’s validators then coordinated to freeze most of the attacker’s funds still on Sui, and the money was returned after an on-chain governance vote. The funds were recovered, but the fact that “validators can freeze anyone’s money” caused major controversy.
The object model and the fast path
On Sui everything is an object: a coin, an NFT, a pool inside a contract are each a numbered object with an owner. There are two kinds:
- Owned objects belong to a single address, such as the coins in your wallet. A transaction that only touches your own things (such as a transfer to someone) cannot conflict with anyone, so it takes effect once validators sign it, without entering network-wide ordering.
- Shared objects can be touched by many people, such as a DEX liquidity pool. Transactions that touch them must go through consensus ordering, so two people cannot buy the same coins at once.
That way, large numbers of simple transfers go through the fast path and only transactions that genuinely need coordination wait in line. Measured, a checkpoint (Sui’s equivalent of a block) comes about every 234 ms, and there are 125 active validators.
- 01Signed and sent
The transaction states which objects it uses. Fees are paid in SUI.
Instant - 02Routed
Transactions touching only owned objects take the fast path; those touching shared objects go to consensus ordering.
- 03Validator signatures / consensus
Fast path: confirmed once validators with over two-thirds of stake sign. Shared objects: executed after Mysticeti consensus sets the order.
Usually under a second - 04Executed, effects produced
Objects are modified, transferred or created, and a certificate of the transaction's effects is produced.
- 05Included in a checkpoint
The transaction goes into the next checkpoint and syncs across the network.
About one checkpoint every 234 ms
SUI and the storage fund
- Fees have two parts: a computation fee (to validators) and a storage fee.
- The storage fee goes into a “storage fund” that subsidises validators who keep this data in the long run. If you later delete on-chain data (for example by destroying an object), most of the storage fee is refunded.
- SUI has a fixed supply of 10 billion. About 4.12B are in circulation, a market cap of $4.28B. The locked remainder is released gradually on a schedule.
What is on-chain today
- USDT 2% $8.9M
- USDC 68% $340.6M
- Other 30% $151.3M
Sources: CoinGecko (market cap, supply), DefiLlama (TVL, stablecoins, DEX volume, fees, protocols), measurements from public nodes (block time, validators).
Things worth noticing:
- Mainly lending and staking: lending protocols such as NAVI and Suilend, plus liquid staking such as SpringSui and Haedal.
- Stablecoins are mainly USDC, with very little USDT.
- More than an order of magnitude smaller than Solana: $508.6M locked and $47.6M of 24-hour DEX volume.
Strengths and trade-offs
- Fast confirmation: simple transfers take the fast path, and complex transactions usually confirm within a second.
- Move builds "assets cannot be copied or vanish" into the language rules, making one class of common contract bugs harder to write.
- Refundable storage fees encourage cleaning up on-chain data.
- Just over a hundred validators, and the Cetus episode showed they can coordinate to freeze funds; decentralisation is limited.
- Not EVM-compatible: Ethereum tools and contracts cannot be used directly, and developers and users have to relearn.
- A large amount of SUI is still locked, and ongoing releases weigh on the price.
- 01
Who holds the TreasuryCap (minting right)? Its holder can mint more of the coin at any time; supply is only fixed once it is renounced or destroyed.
- 02
Is there a DenyCap? Its holder can blacklist anyone so they cannot move the coin.
- 03
Has the package's UpgradeCap been destroyed? If not, the contract logic can be swapped at any time.
- 04
Among the top ten holders, exclude pools and exchanges first, then check whether the rest come from the same source.
- 05
Check DEX pool depth. After the Cetus incident some pools were very thin for a while.
Data and sources
- Live figures: CoinGecko, DefiLlama and a public Sui full node (measured checkpoint interval, active validators).
- Mechanisms are based on the official Sui documentation; the Cetus incident on announcements from Cetus and the Sui Foundation.
- This guide is educational and is not investment advice.
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