What Is a DEX?
A DEX, a decentralized exchange, is a set of smart contracts that lets people swap tokens directly from their own wallets. No account, no signup, no company holding your money. Uniswap on Ethereum and Raydium on Solana are the classic examples. Connect a wallet, pick two tokens, swap.
How It Actually Works
Most DEXs do not match buyers with sellers the way a stock exchange does. Instead, they hold liquidity pools, big shared pots of two tokens, and a formula sets the price based on the ratio in the pot. Your swap trades against the pool. The bigger the pool relative to your trade, the closer you get to the quoted price. The smaller it is, the more slippage you eat.
Risks and Common Mistakes
- Anything can list. Nobody screens tokens on a DEX. Scam tokens with famous names are everywhere. Always verify the contract address.
- Token approvals linger. Swapping requires granting contracts permission to move your tokens. Malicious approvals drain wallets. Review and revoke them periodically.
- No support desk. Send to the wrong token, get sandwiched, buy a honeypot: there is nobody to call.
When It Matters
DEXs are where new tokens trade first, which makes them the natural habitat of memecoins and the tools that track them. They are also core DeFi infrastructure; my DeFi page puts them in context.