Sandwich Bot Crypto: A Plain-English Guide to How These Bots Work

A sandwich bot in crypto is automated software that watches pending transactions on a blockchain, spots a large swap on a decentralised exchange, and places one trade just before it and one just after. The victim’s own trade moves the price, the bot sits on both sides of that move, and the difference, minus fees, is the bot’s gross result. That is the whole mechanism, and everything else in this guide is about the details: how the ordering is achieved, what it costs, how often it goes wrong and who pays.

It helps to be blunt about the economics. The profit does not come from the market in some abstract sense. It comes from the slippage a trader was willing to accept. Set a loose limit and you leave room for a bot to fit its trades inside it. That is why the same topic matters to two audiences: people who operate bots, and people who just want to swap tokens without being taxed by one.

For operators, the practical question is what a product actually offers. CryptoMEV Bot’s sandwich bot page describes software that scans for large swaps with high slippage tolerance, simulates whether the expected slippage profit exceeds the gas cost of the two transactions, and then executes. It says the software is non-custodial and lists a Retail Trader licence at $1,999 one-time and an Enterprise tier from $50,000. It gives no profit figures, and neither do we. If your interest is Solana specifically, its Solana MEV bot page covers Jito bundle support, and its short explainer on what an MEV bot is puts sandwiching in the wider family of MEV strategies.

Start where your question starts.

• New to the idea? Read what a sandwich attack is and then how a sandwich bot works step by step.
• Thinking of running one? Compare what a sandwich bot costs, whether sandwich bots are profitable and whether to build or buy. Read the risks before any of them.
• Worried about the legal side? See whether sandwich trading is legal. The honest answer is that it depends on jurisdiction and facts.
• A trader who wants to stay safe? Use the guides on avoiding sandwich attacks and checking whether you were sandwiched.

Two things to keep in mind throughout. First, this is a competitive, adversarial niche: many operators lose money to failed bundles, gas and rival bots, and no honest source can promise otherwise. Second, rules on market manipulation and on-chain trading are unsettled and changing. Nothing here is financial or legal advice, and every claim about a vendor should be checked on the vendor’s own page.

The Slippage Desk is an independent publication. We name the sources we rely on, mark vendor claims as vendor claims, and discuss alternatives such as plain arbitrage, covered in our guide to sandwich bot alternatives.