What Is MEV?
MEV (Maximal Extractable Value) represents profit that can be extracted by manipulating transaction ordering. When you submit a transaction, bots scan the public mempool and exploit your trade for profit.
MEV Extraction Scale
Types of MEV Attacks
Frontrunning
Bot sees your trade, submits same trade before you with higher gas. Gets better price, you get worse price. Common on large swaps.
Sandwich Attack
Bot buys before you (frontrun) → your trade executes at worse price → bot sells after (backrun). You're the meat in the sandwich.
Backrunning
Bot trades immediately after you to capture arbitrage opportunity your trade created. Less harmful than frontrunning but still extracts value.
Who Gets Attacked?
Any trade in the public mempool is vulnerable. Large swaps, NFT mints, and DeFi interactions are prime targets. Even $100 trades get sandwiched if profitable.
Protection Methods
Flashbots Protect
Sends transactions directly to validators, bypassing public mempool. Bots can't see your trade to frontrun it.
MEV-Share
Allows backrunning but shares profits with you. Get kickbacks from any MEV your trade generates while staying protected from frontrunning.
Batch Auctions (CoW Swap)
All orders in a batch execute at the same price. No transaction ordering = no frontrunning possible.
Intent-Based (UniswapX)
Express trade intent, solvers compete to fill at best price. Competition protects you from MEV.
DEXs with Protection
Setting Up Protection
Quick Setup Guide
Add https://rpc.flashbots.net to MetaMask as custom RPC
Trade on CoW Swap, 1inch Fusion, or UniswapX
Check your tx isn't in public mempool before confirmation
Interactive MEV Protection Demo
Explore MEV protection methods and their trade-offs:
Bot front-runs your swap, then back-runs to profit from your slippage
MEV Risk Level
2/6
Est. MEV Exposure
$25
Protection Status
Exposed
Sandwich Attack Protection
Use private RPC, lower slippage, smaller trades
MEV Protection Checklist
Related Articles
Frequently Asked Questions
MEV (Maximal Extractable Value) is profit extracted by reordering, inserting, or censoring transactions in a block. Validators and searchers capture MEV through frontrunning, sandwich attacks, and arbitrage. It costs regular users through worse execution.
A sandwich attack places a buy before your trade (frontrun) and a sell after (backrun). The attacker buys first, pushing up the price. Your trade executes at the higher price. Then they sell, profiting from the price difference you created.
Flashbots Protect sends your transaction directly to validators through a private channel, bypassing the public mempool. Searchers can't see your tx to frontrun it. Your trade is included without public exposure.
MEV-Share lets searchers backrun your transaction (capturing some MEV) but shares the profit with you. You get protected from frontrunning while receiving kickbacks from any MEV your trade generates. Best of both worlds.
CoW Swap uses batch auctions (no frontrunning possible). 1inch Fusion routes through protected relays. UniswapX uses intent-based trading with solver competition. All provide better execution than standard public mempool swaps.