About

Uniswap is a decentralized exchange (DEX) operating on blockchain networks, enabling users to trade cryptocurrencies through automated liquidity pools. It uses smart contracts to facilitate token swaps without intermediaries and supports decentralized finance (DeFi) applications.

History

Uniswap was born out of an idea proposed in 2016 by Vitalik Buterin for a decentralized exchange (DEX) that would employ an onchain automated market maker (AMM) with certain unique characteristics. A year later, Hayden Adams began working on turning this idea into a functional product, Uniswap V1. After receiving $100,000.00 from the Ethereum Foundation, Uniswap launched in November 2018. Six months after launching, a fundraising round was completed, led by Paradigm, to grow Uniswap Labs’ headcount.

The protocol was built to solve the problem of high spreads for illiquid assets on order-book exchanges. This problem exists because there is little incentive for professional market makers to provide liquidity on thinly traded assets. However, with Uniswap, anyone can be a market maker by depositing assets into a pool and earning fees based on the amount of trading activity.

Uniswap's second iteration, Uniswap V2, launched in May 2020. It introduced ERC-20/ERC-20 swaps (the first version required ETH as a base asset), price oracles (enable decentralized and manipulation-resistant onchain price feeds), and flash swaps (removed upfront capital requirements and unnecessary constraints on order-of-operations for multi-step transactions that use Uniswap). The full details of this upgrade are specified here.

Uniswap V3 was launched in May 2021. The main upgrade from Uniswap V2 to V3 was concentrated liquidity, which gives individual liquidity providers (LPs) granular control over what price ranges capital is allocated. V3 also introduced multiple fee tiers, allowing LPs to be appropriately compensated for taking on varying degrees of risk per asset pair. The full details of this upgrade are specified here.

Uniswap V3 has been deployed on Ethereum, Arbitrum, Optimism, Polygon PoS, Celo, BNB Smart Chain, Avalanche, Base, zkSync, and Scroll. Additional proposals have been accepted to deploy Uniswap V3 on Polygon zkEVM, Linea, Moonbeam, Gnosis, and Boba Network. Of note, these deployments have not been launched.

Regarding Uniswap V4, the project team has stated, "The contracts in this repo are in early stages," and "We are releasing the draft code now so that V4 can be built in public, with open feedback and meaningful community contribution."

UniswapX was launched in July 2023. As of January, 2024, it is only available on Ethereum but is planned to be launched on additional EVM-compatible networks in the future.

In October 2023, Hayden Adams announced that Uniswap Labs would begin charging a 0.15% flat swap fee on specific tokens “when traded through Uniswap Labs interfaces on mainnet and supported [Layer-2s].” As of January, 2024, specified tokens include ETH, USDC, WETH, USDT, DAI, WBTC, agEUR, GUSD, LUSD, EUROC, and XSGD. Revenues from this “interface fee” are stated as being used “to sustainably fund [Uniswap Labs’] operations.” Of note, the 0.15% fee applies solely to swaps where both input and output tokens are among the list of specified tokens. The fee is paid in the output token of the given swap.

Source: What are Uniswap Labs' fees?

In October 2023, Uniswap Foundation announced the launch of a testnet version of Uniswap V4 developed by Conduit. The testnet allows developers to experiment with hooks and other new primitives using Uniswap V4 contracts. Based on a commercially reasonable search, Uniswap V4 is slated to launch after Ethereum’s Dencun upgrade (expected to be in Q1 2024).

In January 2024, Uniswap Labs announced that EIP-6963 went live on the Uniswap interface. This upgrade aims to simplify switching between wallets on Uniswap.

In January 2025, the Uniswap Foundation has announced that Uniswap v4 is now available on Ethereum, Arbitrum, Avalanche among other networks.

Following the SEC Investigation into Uniswap Labs from 2024, in February 2025 Uniswap has announced that as of Feb. 24, 2025, the SEC's investigation into Uniswap Labs has been closed, and the SEC is taking no enforcement action.