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DEX aggregator

A DEX aggregator is a service that searches many decentralized exchanges at once for the best swap price and, when needed, splits one trade across several pools.

How it works

The same pair can trade in dozens of pools with different liquidity and prices. An aggregator queries them, works out the best way to fill your trade after slippage and gas, and builds a route. Sometimes going through an intermediate token is cheaper, for example ETH → USDC → the token you want.

On large trades the difference is noticeable: splitting the swap across several pools means each part moves the price less. Many aggregators also offer MEV protection or a mode where third parties fill your order at a set price.

An aggregator is one more smart contract that you allow to spend your tokens. If it is hacked while you still have an unlimited approval, you can lose those tokens. Some aggregators charge their own fee, usually shown in the route details.

Example with numbers

You swap $50,000 of USDC for a token. A single pool would give 2% slippage, a $1,000 loss. The aggregator splits it: 60% through one pool, 40% through another, for 0.7% total slippage ($350). Even with $15 of extra gas you save about $635.

Common mistake

A common mistake is signing unlimited token approvals for every new aggregator and never revoking them. Approve only the amount of the trade, use the service's official address only, and check and revoke old approvals from time to time.

Questions and answers

What is a DEX aggregator in simple terms?

It is a best-price search engine across many decentralized exchanges. It picks which pools to route your swap through.

Is an aggregator better than a single DEX?

For large trades and less common tokens it usually is, because it cuts slippage. For small swaps in big pairs the difference can be pennies.

Is it safe to use a DEX aggregator?

The risk lies in the smart contract and token approvals. Give limited approvals and use only the official site.

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Updated: 2026-10-19