1inch

1inch functions as a DEX aggregation protocol and multi-chain trading app launched in 2019, offering users and developers unified access to token swap routing across numerous decentralized exchanges and AMM liquidity pools at once. Instead of routing against one pool, 1inch's Pathfinder algorithm scans available liquidity from supported DEX sources on the chosen network and determines the optimal split routing path to minimize slippage while maximizing output for the input token. The trading interface at app.1inch.io enables ERC-20 swaps across Ethereum, BNB Chain, Polygon, Arbitrum, Optimism, Base, Avalanche, Gnosis, zkSync Era, Linea, Sonic, Unichain, Solana, and additional EVM-compatible networks via a single connected wallet

The 1inch ecosystem includes several protocol layers — the Aggregation Protocol for multi-source swap routing, the Limit Order Protocol for conditional on-chain swap execution, and Fusion mode for intent-based order fulfillment where approved resolvers compete to execute swaps. The 1INCH token supports governance via the forum at gov.1inch.network and staking in governance and incentive programs. Protocol elements such as the Aggregation Protocol and Limit Order Protocol are open-sourced under the 1inch GitHub organization, with audit reports available in the github.com/1inch/1inch-audits repository covering contract versions

The main trading flow on 1inch starts at app.1inch.io, where users link an EVM-compatible wallet, pick source and destination tokens on the active network, and obtain a Pathfinder-generated quote detailing expected output, liquidity source splits, estimated price impact, and fees. The interface displays routing choices across different slippage tolerances so users can balance execution reliability against output optimization prior to submitting the on-chain swap transaction. Swaps settle directly against the selected pool contracts on the network without any custodial asset movement during routing or execution

In addition to market swaps, the 1inch interface enables limit order creation via the Limit Order Protocol, allowing specification of input token, output token, price threshold, and expiry that are stored as signed off-chain orders. Keepers monitor and execute these orders on-chain once conditions are met and before expiry, completing the trade atomically without requiring the user to stay online. Fusion mode provides an intent-based alternative where the swap request is submitted for resolvers to compete on filling — resolvers source liquidity through their channels and earn from price improvement rather than user gas fees

The 1inch Aggregation Protocol serves as the primary routing engine that queries on-chain state from supported DEX sources — such as Uniswap, Curve, Balancer, and additional AMMs on each network — to build split trade routes distributing input across multiple pools for superior aggregate output versus any single pool. The Pathfinder algorithm assesses numerous split configurations and selects the route maximizing output given input size and pool conditions, encoding the complete path as atomic on-chain calls in one transaction. This multi-source routing approach lets traders leverage aggregated liquidity across the DEX landscape without manually splitting trades across platforms

The 1inch Limit Order Protocol supplies on-chain infrastructure for conditional swaps, letting users place orders defining exact input amount, minimum output for the target price, and expiry. Orders exist as signed EIP-712 messages off-chain until monitoring detects a fill opportunity, at which point a keeper calls the fill function on the protocol contract to verify the signature and execute the atomic swap if conditions hold. The open-source contracts enable developers to programmatically submit, monitor, and cancel orders via the 1inch API or direct contract interaction

Fusion represents 1inch's intent-based execution approach, where users submit a swap request with desired input, output, and price range without broadcasting a standard on-chain transaction. Approved third-party resolvers that have staked 1INCH compete to fulfill the order by sourcing output liquidity from available on-chain sources and delivering it at or better than specified terms. Resolver competition shifts gas costs away from the user, as the resolver covers execution gas and recoups via achieved price improvement. Fusion orders suit users seeking to minimize on-chain gas exposure while retaining multi-source routing benefits

1inch enables token swaps and Limit Order Protocol execution across numerous EVM-compatible chains including Ethereum mainnet, BNB Chain, Polygon, Arbitrum, Optimism, Avalanche, Base, Gnosis, zkSync Era, Linea, Sonic, Unichain, and others, plus Solana support. The Aggregation Protocol and Limit Order Protocol deploy independently per chain, with chain-specific addresses and DEX source lists detailed in docs.1inch.io. This broad multi-chain reach lets developers and traders access routing and conditional execution on diverse networks without bridges for single-network operations, with Fusion+ extending cross-chain capabilities

1inch supports diverse DeFi and multi-chain trading scenarios: retail users leverage app.1inch.io for ERC-20 swaps on chosen EVM or Solana networks with Pathfinder-optimized routing to lower slippage versus single-pool DEX trades; yield operators apply the Aggregation Protocol for large token conversions across pools to reduce market impact during rebalancing; traders set limit orders via the Limit Order Protocol to enter or exit at target prices without constant monitoring; developers integrate swap routing, wallet trading features, and protocol token conversions using the 1inch API at docs.1inch.io; and 1INCH holders engage in governance at gov.1inch.network to shape protocol parameters and incentives across supported chains

Developer integration relies on documentation at docs.1inch.io covering the Aggregation Protocol API for quote retrieval and transaction building, the Limit Order Protocol API for order handling, and the Fusion mode API for intent-based flows. The 1inch REST APIs take network and token pair inputs and return routing details including split paths, estimated outputs, and encoded calldata for direct wallet submission without custom contract work. Open-source protocol contracts reside on GitHub at github.com/1inch, while the audits repository at github.com/1inch/1inch-audits supplies security reviews for developers extending the deployed infrastructure

1inch maintains an audits repository at github.com/1inch/1inch-audits with security review reports for the Aggregation Protocol, Limit Order Protocol, Fusion, and other contract versions, offering transparent access to audit history. All protocol contract code is publicly available on GitHub under the 1inch organization for independent review. As a non-custodial protocol, 1inch never holds user assets between transactions — swaps execute atomically via the routing contract in a single on-chain transaction with no intermediate custody. Users should consult official resources at help.1inch.com and follow standard Web3 practices such as verifying approvals and calldata before confirming swaps

1inch delivers DEX aggregation for multi-chain ERC-20 and Solana token swap routing, on-chain conditional execution via the Limit Order Protocol, and intent-based fulfillment through Fusion, with core components open-sourced and audits publicly archived on GitHub. The Pathfinder algorithm, deployments across Ethereum and numerous other EVM networks plus Solana, and comprehensive REST API support equip developers and traders with structured tools for integrating routing and order execution into apps and protocols. Evaluators should review docs.1inch.io, the audits repository at github.com/1inch/1inch-audits, and help.1inch.com to assess integration needs, security documentation, and resources before building on or trading via the protocol