How many SUI tokens are there?

There are exactly 10,000,000,000 SUI (10 billion), and that number never changes. The whole supply was minted at genesis, and the Sui framework has no way to mint more. The circulating supply is smaller. About 5% was in circulation at mainnet launch, and the rest is released over time on a schedule the Sui Foundation publishes. In the smallest unit, the total is 10^19 MIST, since 1 SUI = 10^9 MIST.

Where the number comes from

The cap is a constant in the sui::sui framework module:

Move

/// The total supply of Sui denominated in whole Sui tokens (10 Billion)
const TOTAL_SUPPLY_SUI: u64 = 10_000_000_000;

/// The total supply of Sui denominated in Mist (10 Billion * 10^9)
const TOTAL_SUPPLY_MIST: u64 = 10_000_000_000_000_000_000;

At genesis, sui::sui::new creates the currency, increases its supply by TOTAL_SUPPLY_MIST once, then destroys the Supply object. It also checks it is running in epoch 0 from the system address. With no treasury cap or supply left, nobody can mint more SUI. Stake rewards don't create new tokens either. The stake subsidy is paid from a pool of SUI set aside at genesis (see SUI tokenomics).

Total vs circulating supply

Measure	What it means
Total supply	10 billion SUI, fixed by the framework
Circulating supply	Tokens that have unlocked and can move freely
Locked / unvested	Allocations still on vesting schedules (Community Reserve, early contributors, investors, Mysten Labs treasury)
Stake subsidy pool	SUI held in the system object and paid out to stakers each epoch

The Sui Foundation says the long-run circulating supply is the full 10 billion, and that releases happen periodically "on a proposed schedule" based on the network's needs. Its token schedule page has the current unlock chart. Circulating supply isn't a protocol constant, so we don't quote a figure here. Check the Foundation's page for the latest numbers.

Check it onchain

The supply recorded in the SUI coin metadata is the total supply, in MIST:

Terminal

curl -s https://graphql.mainnet.sui.io/graphql \
  -H 'content-type: application/json' \
  -d '{"query":"{ coinMetadata(coinType: \"0x2::sui::SUI\") { supply decimals } }"}'

As of epoch 1291 (2026-10-25), mainnet returns "supply": "10000000000000000000" with "decimals": 9.

You can see how much SUI is still in the stake subsidy pool with the TypeScript SDK:

TypeScript

import { SuiGrpcClient } from '@mysten/sui/grpc'

const client = new SuiGrpcClient({
  network: 'mainnet',
  baseUrl: 'https://fullnode.mainnet.sui.io:443',
})

const { systemState } = await client.getCurrentSystemState()
const MIST_PER_SUI = 1_000_000_000n
console.log(BigInt(systemState.stakeSubsidy.balance) / MIST_PER_SUI, 'SUI left for subsidies')

At epoch 1291 that pool held about 225.97 million SUI.

Gotchas

Explorers and data sites define "circulating" differently. Some count staked SUI, some subtract Foundation-held tokens. Compare their methods before trusting a number.
SUI amounts in code are u64 MIST values. 10 billion SUI (10^19 MIST) fits in a u64, whose maximum is about 1.8 × 10^19, but sums can overflow in JavaScript number. Use bigint.

Sources

sui::sui module source, MystenLabs/sui on GitHub
Tokenomics, Sui documentation
SUI token supply and circulation, Sui Foundation