CEX versus DEX: trading with an exchange account or a wallet

Not every place where you swap coins works the same way. A centralized exchange, or CEX, has an operator managing accounts and trading systems. A decentralized exchange, or DEX, uses blockchain programs and related mechanisms. The biggest practical differences are how assets are held and how trades are processed.

CEX: account-based trading

• Access: Sign in to an exchange account. Identity verification may be required, depending on the service.
• Custody: The exchange generally controls the private keys for deposited assets.
• Execution: Buy and sell orders are matched in the exchange's system. Not every trade is individually recorded on a blockchain.
• Checks: The operator's reliability, fees, supported deposit and withdrawal networks, withdrawal limits and maintenance status.

DEX: wallet-based trading

• Access: Usually connect a personal wallet, review the transaction and sign it.
• Custody: Users often manage their own private keys or recovery phrases.
• Execution: Designs vary, including automated market makers using liquidity pools and on-chain order books.
• Checks: Official addresses, contract permissions, gas fees, liquidity, slippage and price impact.

A DEX is not necessarily free of operator or administrator powers. Its website, upgrade authority or parts of transaction processing may depend on particular parties. The label “centralized” or “decentralized” alone cannot determine safety.

Spending the same ₩100,000 can buy different quantities

On a CEX, quoted orders and trading fees affect the outcome. On a DEX, pool prices, trade size and network costs matter. Comparing only the displayed price per token can hide the real cost. If you plan to withdraw or transfer the asset, check those costs and supported networks separately.

Your options after a mistake differ, too. A CEX has customer support, but recovery is not guaranteed. Once a DEX transaction is final, operators often cannot simply cancel it. Whichever route you use, check the amount and recipient or target before confirming an order or signature.

References

ethereum.org
docs.uniswap.org