Sei (SEI)

Sei (SEI) is the native cryptocurrency of Sei, a layer-1 blockchain built for fast trading and other financial applications. SEI pays transaction fees, is staked to secure the network and is used to vote on its governance proposals. The network went live in August 2023 and has since repositioned itself as a high-speed chain compatible with the Ethereum Virtual Machine (EVM).

Sei began life inside the Cosmos ecosystem, alongside chains connected to Cosmos (ATOM), but in 2025 its community voted to drop its Cosmos features and run as an EVM-only network. It competes with other fast chains such as Solana (SOL) and Sui (SUI), and with exchange-focused chains such as Injective (INJ).

Imagine a supermarket where every customer must queue at a single till, even if they are only buying one item. Most early blockchains worked that way, handling transactions strictly one after another. Sei opens many tills at once. When two customers' baskets have nothing to do with each other, they are served at the same time, and the shop only slows down when two people reach for the same item.

That approach is meant to suit trading, where thousands of orders arrive every second and delays cost money. Because Sei speaks the same programming language as Ethereum, developers can move existing Ethereum apps onto it with few changes. SEI is the coin used to pay at the tills, and people who stake it help keep the shop open in exchange for rewards.

Sei was founded by Jeff Feng and Jay Jog, whose company Sei Labs started building the chain in 2022. The Pacific-1 mainnet and the SEI token launched in August 2023, with part of the supply offered through a Binance Launchpool rather than a public sale. In mid-2024 the Sei V2 upgrade added a parallelized EVM, which let Ethereum-style smart contracts run alongside Sei's original Cosmos contracts. In May 2025 the community approved SIP-3, a proposal to remove the Cosmos side entirely; through 2026 the network rolled out upgrades for the change, and in May 2026 it disabled the import of assets over the Cosmos IBC bridge. Sei Labs has also set out a roadmap called Sei Giga, which targets about 200,000 transactions per second.

Sei uses proof of stake and a consensus design derived from Tendermint, a form of Byzantine fault tolerance in which a set of validators vote on each block. Blocks are produced roughly every 400 milliseconds. Its main feature is optimistic parallel execution: the chain runs many transactions at the same moment, checks afterwards whether any of them touched the same data, and reruns only those that clashed. Because it runs the EVM, fees are calculated the same way as on Ethereum:

• $F$ is the fee paid, in SEI.
• $G$ is the amount of gas the transaction uses, a measure of computing work.
• $P$ is the gas price, the amount of SEI paid per unit of gas.

A token transfer that uses 50,000 gas at a price of 0.0000001 SEI per unit costs $50{,}000 \times 0.0000001 = 0.005$ SEI. See gas fee for the general idea.

SEI has a fixed maximum supply of 10 billion tokens. According to Sei's published tokenomics, 48 percent was set aside as an ecosystem reserve for staking rewards, grants and incentives, 20 percent went to the team, 20 percent to private investors, 9 percent to the foundation and 3 percent to the Binance Launchpool. Team and investor tokens unlock gradually after a one-year cliff; see token unlock. Its main uses are:

• Fees. Every transaction on the network is paid for in SEI.
• Staking. Holders can delegate SEI to validators and earn a share of rewards; see staking.
• Governance. Staked SEI is used to vote on proposals such as SIP-3.
• Trading. The chain hosts decentralized exchanges, lending markets and stablecoins such as native USDC.

Sei faces crowded competition from other parallel-execution chains, and much of its headline speed comes from roadmaps rather than sustained real-world demand. A large share of the supply belongs to insiders and the ecosystem reserve, so scheduled unlocks add selling pressure over time. The shift away from Cosmos was also disruptive: users holding IBC assets or Cosmos-based tokens such as the bridged USDC.n were told to move them before support ended, or risk losing access. As with other proof-of-stake chains, the validator set is far smaller than the number of token holders, which concentrates control. Sei has also suffered from the general problem of fast chains: impressive test results do not guarantee that real users and liquidity will follow, and activity on the network has risen and fallen with incentive programmes.

• Sei
• Sei documentation