1. Get protected
  2. FAQ

The best MEV protection under the sun

MEV Blocker is your personal protection from frontrunning and sandwich attacks for a broad spectrum of Ethereum transactions

  1. Add the RPC endpoint directly to your wallet
  2. Enjoy full, automatic protection from all types of MEV
  3. Get paid by searchers for your transactions
Get Protected

Broad spectrum
MEV defense

MEV bots have extracted more than $1.38 billion from well-meaning Ethereum users across a variety of use cases (trading, providing liquidity, minting NFTs, etc). MEV Blocker is an RPC endpoint that supports these users by offering:
Full protection from frontrunning and sandwich attacks on all types of transactions

Full protection from frontrunning and sandwich attacks on all types of transactions

Profit from any backrunning opportunities your transactions create

Profit from any backrunning opportunities your transactions create

A fast, free, censorship-resistant solution open to all searchers and builders

A fast, free, censorship-resistant solution open to all searchers and builders

Get protected

Add this RPC endpoint to your wallet to enjoy the full benefits of MEV Blocker

Click to add to your client

MEV Blocker (Ethereum Mainnet)

Add to Wallet

Or manually add:

Network NameMEV Blocker (Ethereum Mainnet)
Chain ID1
Currency SymbolETH
Block Explorer URL

Having trouble? Check your wallet's documentation
for instructions on how to update your RPC endpoint


What is MEV?
MEV or “maximal extractable value” is a method used by savvy actors (known as “searchers”) to exploit your transactions at your expense.

Any time you make a transaction that carries value, searchers can “frontrun” it by submitting the exact same transaction before you and keeping the profits for themselves. After getting frontrun, you can also get “backrun”, which is where the searcher cleans up any price slippage your trade caused, again keeping the profits for themselves. Both a frontrun and a backrun together are known as a “sandwich attack” — the worst type of MEV.

MEV gives you a worse price for your transactions and can cause you to lose out on hundreds or even thousands of dollars. MEV Blocker is an easy solution - an RPC endpoint that protects all types of transactions from MEV.
What is an RPC endpoint?
An RPC (remote procedure call) endpoint is used to connect applications like wallets to the blockchain.

MEV Blocker is a special RPC endpoint that ensures your trades are protected from MEV. It does this by sending your transaction to a network of searchers that scan for backrunning opportunities, but cannot frontrun or sandwich your trades.

You can add RPC endpoints like MEV Blocker by changing the selected network in your crypto wallet. Some DeFi trading apps will also be able to integrate the MEV Blocker RPC endpoint directly — making it a default for all users. Get in touch if you're interested in doing this!
What kinds of MEV does MEV Blocker protect from?
MEV blocker protects from most kinds of frontrunning, but especially from trade sandwiching, which is when a searcher trades just before and just after your transaction to make a profit.
How does MEV Blocker RPC give you a rebate and when?
MEV Blocker also lets you benefit from backrunning. It does this by allowing searchers to “bid” in an auction to win the right to backrun your trade. When this happens, users of MEV Blocker receive 90% of the profit their backrunning opportunity creates (compared with 0% when not using MEV Blocker).The rebate is paid to the user that sent the transaction (tx.origin), immediately in the same block.

In return for benefitting from backrunning your trade, these searchers are not allowed to frontrun or sandwich you — thus protecting you from the worst types of MEV.
When and where should I use MEV Blocker?
You should use MEV Blocker as often as possible!

While some DEXs like CoW Swap offer MEV protection for your DeFi trades, most DeFi venues and NFT marketplaces do not provide any type of MEV protection.

This is where MEV Blocker comes in: any user or dApp can implement it and it protects all types of transactions from MEV.

See a chance to mint the next Cryptopunks but don't want anyone to snatch the opportunity from you? Use MEV Blocker.

Want to trade directly on an AMM that doesn't protect you from MEV? Use MEV Blocker.

And more!
How do I install MEV Blocker?
To use MEV Blocker, you will need to add the MEV Blocker RPC endpoint to your wallet. You can do that easily by following the instructions here. (Note that once your MEV Blocker is added to your wallet, you might need to check that it is your selected network from time to time.)

If your wallet does not support adding custom RPC endpoints, you may have to contact your wallet developer to get MEV Blocker included as a supported RPC.
How does MEV Blocker work?
MEV Blocker facilitates an auction between a network of “searchers” who are given the opportunity to backrun your transactions. In return, they protect you from frontrunning and sandwich attacks - the nasty types of MEV that exploit Ethereum users every day.

When searchers submit winning bids through the orderflow auction, MEV Blocker sends the full amount of the bid to users and validators at a 90/10 split. Validators keep the 10% as a reward, and users pocket the other 90% as profit they'd miss out on if they weren't using MEV Blocker.

As long as you have MEV Blocker set as the RPC in your wallet (as if it were another network), you are protected from frontrunning and sandwiching when using any Ethereum dApp. And the profit share from backrunning is deposited automatically into your wallet.
Which block builders does MEV Blocker submit to?
MEV Blocker submits to all major block builders, including Builder0x69, f1b, Flashbots, rsync builder, Titan Builder, Gambit labs and Beaver Build.
Does this RPC offer revert protection?
No, this RPC focuses on fast execution, however, we are offering another endpoint which offers revert protection.

This separate endpoint focuses on providing revert protection first, at the expense of possibly slower inclusion time. You can use this second endpoint by using as the url instead.
Does this RPC offer a secure & private RPC endpoint?
Yes! if you want your transactions to be completely private, and you don´t care about the refund, you need to connect to the following endpoint: as the url instead.

This endpoint focuses on privacy for users that want to perform transactions and it will not share TX data over WS. It prevents transactions failures (same as /noreverts).

Note: This endpoint is intended for sophisticated users who can unstuck transaction themselves.
While using MEV Blocker RPC, is it safe to ignore slippage control??
NO, you should ALWAYS set slippage control to have multiple protections in place.

Goal of RPC is to prevent 99% of sandwiches but no existing solution can provide full 100% protection. Due to reorgs/forked blocks 0.1% of transactions might become publicly available before on-chain confirmation.
Who made MEV Blocker?
MEV Blocker is jointly formulated and maintained by CoW Protocol, Agnostic Relay, and Beaver Build. It is open to all searchers and block builders.

This collaboration represents our commitment to providing a trusted, neutral product available to all Ethereum users. We invite additional contributors - please get in touch if you're interested in supporting the project.
How do I participate as a searcher?
If you are a searcher that is interested in collaborating with MEV Blocker RPC, please check out the documentation for searchers and join the community.
How can I get in touch?
If you are a searcher or a dApp developer, or if you're a user that has questions about MEV Blocker, please reach out via Telegram.

What others are saying...

MEV Blocker fixed my marriage - Anon

I was tired of getting rekt, so I started using MEV Blocker - Anon

If I'd known about MEV Blocker sooner, I could've had a lambo by now - Anon

Robots should work for me, not against me - Anon

Nobody's stolen my lunch money since I started using MEV Blocker - Anon

I used MEV Blocker and I instantly went up a tax bracket - Anon

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Launch partners

CoW Swap
Aura Finance
Titan Builder