Before you use a DEX: a safety checklist
No customer support and no undo button. Check before you swap.
Before swapping on a decentralized exchange (DEX), open the real site from a bookmark, confirm you're on the right network with a little of its coin for fees, pick tokens by contract address rather than name, check price impact and keep slippage low, approve only the amount you're swapping, and review the final screen. A small test swap is cheap insurance.
Legitimate support will never ask for your seed phrase (recovery phrase) or private key. Not an exchange, a wallet maker, a lawyer, the police or the FBI. Anyone who asks for it, or asks you to type it into a website, is trying to steal from you.
The checklist
Tick each step as you go. Use the print button for a paper copy to keep by your computer.
All 11 checked. If anything along the way felt wrong, trust that feeling and wait.
Your ticks are saved only in this browser, so you can come back to them. Nothing is sent anywhere.
Why these checks matter
A DEX is a set of smart contracts: there's no company to reverse a wrong trade, and the front end you see could be fake. Most DEX losses come from lookalike sites, fake tokens with familiar names, high slippage and leftover approvals, not from the swap itself. Learn more in what is DeFi? and smart contract exploits.
Frequently asked questions
What is slippage on a DEX?
The difference between the quoted price and the price you actually get. Your slippage setting is the most you'll accept; set it low to avoid bad fills and sandwich attacks.
Why did my swap fail but still cost a fee?
Network fees pay for the attempt, so a swap that fails, for example because the price moved beyond your slippage limit, still costs gas.
Where to next
Sources
Written for beginners and checked against the sources listed. Last reviewed November 5, 2026. This page is educational and is not financial, tax or legal advice. How we write and check pages.