1inch: The DEX Aggregator That Finds Your Best Price
1inch Network scans 400+ liquidity sources across 12 chains to find the optimal swap route, saving traders an average of 1–5% per trade compared to using a single DEX.
How 1inch Works
1inch's Pathfinder algorithm evaluates thousands of possible routes in milliseconds, selecting the combination that maximizes your output tokens after accounting for gas costs and price impact.
Pathfinder v2 Algorithm
Pathfinder v2 is a graph-traversal algorithm that models all DeFi liquidity as a weighted directed graph, then finds the minimum-cost path from input to output token.
Every pool across all supported DEXs becomes a node. Edge weights encode fee tier, current reserves, and estimated gas cost to traverse that hop.
Pathfinder evaluates direct swaps, two-hop routes (e.g. TOKEN → ETH → USDC), and multi-split paths where trade value is divided across several pools simultaneously.
Each additional hop or split costs extra gas (~15–50k gas per step). Pathfinder only adds a route split when the price improvement exceeds the incremental gas cost — at current ETH prices and gas levels.
The optimal combination is returned as a calldata bundle. One transaction, multiple DEX interactions, atomic execution. If any hop fails, the entire trade reverts.
Gas Cost vs. Savings Tradeoff
Extra routes improve price but cost more gas. Drag to see the breakeven point for your trade size.
1inch Fusion Mode — Gasless Swaps
Fusion mode lets you swap tokens without paying any gas fee yourself. Instead of broadcasting a transaction, you sign an off-chain intent and a network of "resolvers" compete to fill it.
Off-chain EIP-712 signature: "Swap 1 ETH for at least 3,250 USDC, expires in 60s." Zero gas paid by you.
Starting price is above market. The offered rate decays over 60–120 seconds, making it increasingly profitable for resolvers to fill.
A registered resolver pays the gas and executes the swap when their profit margin is sufficient. They earn the spread between auction price and execution cost.
Tokens arrive at your wallet. You paid zero ETH in gas. MEV bots cannot front-run because the order is filled by whitelisted resolvers only.
1inch vs Direct DEX — When Does It Actually Help?
1inch adds meaningful value for large trades and exotic pairs, but for small swaps on major pairs, a direct Uniswap transaction is simpler, cheaper, and equally good.
| Scenario | 1inch | Direct Uniswap | Verdict |
|---|---|---|---|
| Swap $500 ETH → USDC | ~0.1% better price, +$10–20 extra gas | Single pool, predictable, lower gas | Use Direct |
| Swap $50,000 ETH → USDC | Splits across 3–4 pools, saves $200–400 | 0.3–0.6% price impact on single pool | Use 1inch |
| Swap $500,000 WBTC → DAI | 5–8 routes, saves $3,000–8,000+ | Severe price impact, likely >1% | Use 1inch |
| Swap ETH → obscure altcoin | Finds all pools including Curve + Balancer | Only Uniswap pools, may miss best price | Use 1inch |
| Swap stablecoins (USDC → USDT) | Routes to Curve (optimal), minimal diff | Curve is accessible directly too | Either works |
| Gasless swap (Fusion mode) | Zero gas, MEV protection, slower | Requires gas, MEV-exposed | Use 1inch Fusion |
Try 1inch
Ready to get the best swap price? Start with 1inch, then explore our tools to optimize your DeFi strategy.
Swap tokens across 400+ liquidity sources. Connect your wallet and get the best route instantly.
Swap ETH gaslessly. Sign an intent and let resolvers compete to fill your order.
Calculate gas costs for multi-hop routes. Find out if 1inch actually saves you money for your trade size.
Moving assets cross-chain? Compare bridge fees and speeds before you swap on the destination chain.
Frequently Asked Questions
Is 1inch safe to use?
1inch is one of the most battle-tested aggregators in DeFi, having processed over $400B in cumulative volume since 2019. The contracts are audited by multiple security firms. That said, no smart contract is risk-free — always verify the token contract and use reasonable slippage settings. Fusion mode reduces on-chain risk by having resolvers execute on your behalf.
Does 1inch charge fees?
1inch charges a small swap fee (typically 0.1–0.3% depending on token and chain) built into the routing. For Fusion mode swaps, resolvers compete to fill your order — they earn the spread, so the effective fee is the difference between quoted and executed price. There is no explicit fee for using the interface.
How much can I save using 1inch?
Savings range from near-zero (small trades on major pairs like ETH/USDC) to 1–5% for large trades on less liquid pairs. The breakeven point is roughly $5,000–$10,000 on Ethereum mainnet, where the gas cost of multi-hop routing starts being outweighed by the price improvement. On L2s (Arbitrum, Polygon), the threshold drops below $1,000.
What chains does 1inch support?
As of 2024, 1inch supports 12+ chains: Ethereum, BNB Chain, Polygon, Arbitrum, Optimism, Avalanche, Fantom, Gnosis, zkSync Era, Base, Linea, and Aurora. Fusion mode is available on Ethereum and is expanding to major L2s.
1inch vs Uniswap — which should I use?
Use 1inch for trades above ~$10,000, exotic token pairs with fragmented liquidity, or when you want gasless execution via Fusion mode. Use Uniswap directly for small swaps on major pairs (ETH, USDC, WBTC) where you want maximum simplicity and predictable behavior. For MEV-sensitive trades, CoW Swap is also worth considering alongside 1inch.