What Is 1inch? How the DEX Aggregator Works and How to Use It

1inch is a decentralized exchange (DEX) aggregator. It does not hold a single pool of liquidity that it prices trades against. It scans many DEXs and liquidity sources and builds a route for your swap that aims to give you more tokens out for the tokens you put in.

The project began at a 2019 hackathon and was created by Sergej Kunz and Anton Bukov. It has since grown from a single aggregation contract into a set of products: swaps, limit orders, cross-chain swaps, a wallet, and developer tools. It also has a governance token, 1INCH, and a DAO.

A few points define what 1inch is:

• Non-custodial: your tokens stay in your wallet until a swap executes on-chain. 1inch does not take deposits or run user accounts.
• Multi-chain: it works on many EVM-compatible networks, and the list changes, so check the app for current support.
• Aggregator, not a market maker: the liquidity comes from other protocols and professional market makers.
• Open to integration: wallets and apps can use its API and contracts to offer swaps inside their own products.

If you have used a single DEX before, think of 1inch as a price-comparison layer on top of many of them.

A single DEX can quote a poor price on a large trade, because its pool has limited depth. Different DEXs hold different pools, and the same pair may be priced slightly differently on each. 1inch searches across those sources at once.

Its routing engine, called Pathfinder, looks for the combination of paths that gives the best net result. Two ideas matter:

• Split routing: one order can be divided across several pools. For example, part may go through one DEX and part through another, which reduces the price impact each pool suffers.
• Multi-hop routing: if there is no good direct pool for a pair, the route may pass through an intermediate token such as a major stablecoin or wrapped native asset.

The engine weighs more than the headline price. More hops and more pools mean more gas, so a route that looks better before gas can be worse after it. The quote you see is meant to reflect the expected result after estimated costs, though the final outcome can shift if the market moves before your transaction confirms.

The same aggregation idea exists on other chains. Pact on Algorand includes a swap aggregator, for example, and DEXs such as SUN.io on TRON and Momentum on Sui each serve their own ecosystem.

1inch offers several ways to trade, each suited to a different need.

Product	What it does
Classic swap	Standard on-chain aggregation. You sign, pay gas, and the route executes in one transaction.
Limit orders	You set a target price and the order fills only if the market reaches it.
Fusion	An intent-based swap. You sign an order, and professional participants called resolvers compete to fill it, often handling gas for you.
Fusion+	Extends the intent model to swaps between different chains, without you using a manual bridge.
1inch Wallet	A self-custody wallet app with swapping built in.
Developer tools	APIs and contracts that let other apps add swaps or price data.

The intent-based modes work differently from a classic swap. You state what you want, and resolvers bid to deliver it, which can help protect against some forms of value extraction. The trade-off is that you rely on resolvers to pick up your order, so execution can depend on market conditions.

The 1INCH token underlies governance of the protocol through the 1inch DAO. You do not need it to trade.

The steps below describe a standard swap. Menu names change over time, so treat them as a guide.

1. Open the official app. Type the address yourself or use a bookmark you created from a trusted source. Do not follow links from ads, direct messages or public reporting you have not checked.
2. Connect your wallet. Choose a wallet you control. Make sure it is on the network you want to trade on.
3. Choose tokens and amount. Select the token you are selling and the one you want. Check the token contract address for anything unfamiliar, since scam tokens copy real names and tickers.
4. Review the quote. Look at the expected output, the minimum received, the route, the price impact, and the estimated network fee.
5. Set slippage. Keep it as low as the trade allows. Very low values can make the transaction fail on volatile tokens.
6. Approve the token if asked. The first time you sell a token, you grant the router permission to spend it. Where possible, approve only the amount you need.
7. Confirm the swap. Read the wallet prompt, sign, and wait for confirmation on the network.

Keep a small amount of the network's native token for gas. Without it, you cannot send a standard transaction, however much of the other token you hold.

Several costs can apply to a swap, and they come from different places.

• Network gas: paid to the blockchain's validators. It rises and falls with network demand and with route complexity. On Ethereum mainnet it can be significant for small trades, while many layer-2 networks cost much less.
• Liquidity source fees: each pool you route through charges its own trading fee, which is already reflected in the quote.
• Price impact: the move in price caused by the size of your trade relative to pool depth. It is not a fee, but it is a real cost.
• Interface or integrator fees: some apps built on 1inch add their own fee. 1inch's own fee policy can change, so read the quote breakdown and the official documentation.

Slippage tolerance is the maximum worsening of price you accept between quote and execution. If the price moves beyond it, the transaction reverts and you lose only the gas spent. A very high setting avoids failures but lets bots or market moves give you a worse fill.

Before a large trade, compare the quote with a single major DEX and look at the net amount after gas. Splitting a very large order over time can also reduce price impact.

1inch is non-custodial, which removes the risk of an exchange holding your funds. It does not remove every risk. Most losses in swaps come from user-side mistakes and token-level scams.

• Fake sites and impersonators: phishing pages copy DeFi interfaces. Bookmark the correct address and never type a seed phrase into a website, ever.
• Scam tokens: anyone can create a token with a familiar name. Verify the contract address through a source you trust, and be wary of tokens you did not look for.
• Open approvals: a token approval stays active until you revoke it. Review and revoke old or unlimited approvals with a reputable approval-checking tool.
• Smart contract risk: every protocol can have bugs, even audited ones. Audits reduce the risk but do not eliminate it.
• MEV and sandwich attacks: bots can profit from the gap between quote and execution. Reasonable slippage and intent-based swap modes can reduce exposure.
• Illiquid tokens: a quote may look fine, but you may not be able to sell later, or the price impact may be severe.

Trade amounts you can afford to lose, test with a small transaction first, and use a hardware wallet for larger balances. Check local rules on trading and taxes in your country.

Choosing between 1inch, a single DEX and a centralized exchange depends on what you value.

• Versus a single DEX: 1inch can give better pricing on larger or less common pairs, because it can split orders and use multiple pools. On a small trade in a deep pool, a direct DEX swap may cost the same or less once routing gas is included.
• Versus a centralized exchange: a centralized exchange such as OKX or Bitget offers an order book, fiat on-ramps, account recovery and support, but you deposit funds with the company and usually complete identity checks. 1inch gives you self-custody and access to on-chain tokens that exchanges may not list, but you handle your own security and gas.

1inch suits people who already hold crypto in a self-custody wallet and want to swap on-chain at a competitive rate. It is less suited to buying crypto with a bank card for the first time, since it is not a fiat on-ramp.

Swapping is only one DeFi activity. Many users then move assets into staking, such as Lido for ETH, or liquidity provision, where managers like Gamma automate concentrated positions. Each adds its own risks, so learn them before you commit funds.

Some details about 1inch change often, so check them at the source rather than relying on a guide, including this one.

• Supported networks and tokens: shown in the app's network selector.
• Fees and fee policy: listed in the official documentation and in the quote breakdown on every swap.
• Product availability: Fusion, Fusion+, limit orders and wallet features can be added, changed or restricted by region.
• 1INCH token details: supply, staking terms and governance rules are in the official docs and DAO forum. Check a reputable market data site for prices, which this guide does not quote.
• Security information: audit reports and any incident notices are on official channels.
• Regional access: availability can depend on your location and local rules. Follow them, and do not attempt to bypass restrictions.

Use only the official site, documentation and verified social accounts, reached through your own bookmarks. Support staff will never ask for your seed phrase or private keys.