MEV Protection
Maximal Extractable Value (MEV) represents value extracted from users through transaction ordering. Understanding and protecting against MEV is essential for preserving your DeFi returns.
What Is MEV?
MEV is profit extracted by reordering, inserting, or censoring transactions within a block. Originally "Miner Extractable Value," now "Maximal Extractable Value" post-merge.
Common MEV Types
Sandwich Attacks: Attacker spots your swap, places a buy before and sell after, profiting from price impact. Front-Running: Seeing your profitable transaction and executing it first. Back-Running: Executing immediately after a transaction to capture opportunities. Liquidation: Racing to liquidate positions and collect rewards.Protecting Yourself
Use MEV-Protected RPCs
Flashbots Protect: Free RPC that sends transactions directly to builders, bypassing public mempool. MEV Blocker: Aggregates multiple builders for better protection and potential rebates.Slippage Settings
Tight Slippage: Reduces sandwich profitability but risks failed transactions. MEV-Aware Slippage: Set slippage just above expected price impact.DEX Selection
CoW Swap: Batch auctions with MEV captured and redistributed to users. 1inch Fusion: Resolver network for MEV-protected swaps. Private Order Flow: Some DEXs route orders to avoid public mempool.Sizing
Smaller Trades: Less attractive targets for sandwiches. Split Trades: Break large swaps into multiple smaller ones.MEV-Resistant Protocols
CoW Swap
- Orders matched off-chain before settlement
- MEV captured and redistributed
- Solver competition for best execution
Flashbots Protect
- Free RPC endpoint
- Private transaction submission
- Simple wallet configuration
MEV Blocker
- Aggregated protection
- Potential rebates from captured MEV
- Easy integration
Quantifying MEV Costs
Studies suggest DEX traders lose 0.5-2% to MEV on typical swaps. Large trades or low-liquidity pairs suffer more.
FAQ
Is all MEV bad?No. Arbitrage MEV improves efficiency. Harmful MEV (sandwiches) extracts value from users.
How much do I lose to MEV?Estimates suggest 0.5-2% on typical swaps. Large trades lose more.
Which protection should I use?Flashbots Protect is a good default. CoW Swap for larger trades.
Related Topics
Explore: [oracle risks](/insights/learn/oracle-risks), [smart contract risks](/insights/learn/smart-contract-risks).
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