What is Front-running?

When someone sees your pending transaction and inserts their own ahead of it to profit at your expense — common on public DEX mempools.

How it works

Your broadcast trade is visible before it confirms, so a bot can buy first, let your trade push the price up, then sell. Tight slippage tolerance and private transaction routes mitigate it.

Example

In practiceYour large buy is spotted in the mempool; a bot front-runs it, and your fill price is worse than quoted.

How do I reduce front-running?

Lower slippage tolerance, split large trades, or use a private/MEV-protected transaction route where available.

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