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How-To GuideSecurityAdvanced

How to Use MEV Protection

Protect your transactions from sandwich attacks and front-running. Use private mempools and MEV blockers.

Estimated reading time20-30 minutes7 stepsPrerequisites: MetaMask or compatible wallet, Understanding of transaction mechanics, Active trading or large swaps

Quick Overview

1
Understand Your Risk
2
Add Flashbots Protect RPC
3
Switch to Protected Network
4
Use MEV-Protected DEXs
5
Set Appropriate Slippage
6
Consider Transaction Timing
7
Verify Protection

How to Use MEV Protection

MEV (Maximal Extractable Value) lets sophisticated actors profit from your transactions through front-running, sandwich attacks, and arbitrage. Protection tools help you avoid these losses.

Types of MEV Attacks

Sandwich Attack:
  1. Bot sees your buy order
  2. Bot buys before you (front-run)
  3. Your order executes at higher price
  4. Bot sells after you (back-run)
Front-Running:

Bots copy your profitable transaction and execute it first with higher gas.

MEV Protection Options

ToolMethodCost
. . .. . . .. . .
Flashbots ProtectPrivate mempoolFree
MEV BlockerOFA auctionFree
CowswapBatch auctionFree

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Step-by-Step Instructions

1

Understand Your Risk

MEV impacts large swaps most. Trades under $1k rarely attract MEV attention.

Tips

  • Larger trades = more MEV risk
  • Popular tokens targeted more
  • Low liquidity pools more vulnerable
2

Add Flashbots Protect RPC

Add Flashbots RPC to MetaMask: Settings → Networks → Add Network.

Tips

  • RPC URL: rpc.flashbots.net
  • Same chain ID as Ethereum (1)
  • Free to use
3

Switch to Protected Network

When making large swaps, switch to Flashbots network in MetaMask.

Tips

  • Transactions go to private mempool
  • Not visible to MEV bots
  • Switch back after
4

Use MEV-Protected DEXs

Cowswap and 1inch Fusion have built-in MEV protection.

Tips

  • Cowswap batches orders
  • 1inch Fusion uses resolvers
  • No RPC change needed
5

Set Appropriate Slippage

Lower slippage reduces MEV opportunity but may cause failed transactions.

Tips

  • 0.5% for stable pairs
  • 1-3% for volatile pairs
  • Do not set unnecessarily high
6

Consider Transaction Timing

MEV is most active during high-volume periods. Off-peak may have less MEV.

Tips

  • Less competition = less MEV
  • Not guaranteed protection
7

Verify Protection

Check that transactions are going through protected routes.

Tips

  • Flashbots explorer shows private txs
  • Compare execution vs quote

Frequently Asked Questions

Related Resources

Protocols

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