Centralized vs. decentralized exchanges (CEX vs. DEX), and brokers
Three very different ways to trade crypto, and what you're trusting with each one.
A centralized exchange (CEX) is a company that holds your money and crypto and matches your orders on its own books. A decentralized exchange (DEX) is a set of smart contracts you trade with directly from your own wallet, with no account and no company holding your funds. A broker sells you crypto at a price it quotes, often inside an app, and may not let you withdraw. The trade-off is simple to state: with a CEX or broker you trust a company; with a DEX you trust code and your own care.
The three models in one table
| Compare | Centralized exchange (CEX) | Decentralized exchange (DEX) | Broker or app |
|---|---|---|---|
| Who holds your funds | The exchange | You, in your own wallet, until the moment of the swap | The broker (or its custodian) |
| How prices are set | An order book: buyers' and sellers' orders meet | Usually a pool of two tokens priced by a formula; sometimes an on-chain order book | The broker quotes a price that includes its margin (the spread) |
| Account and ID | Account with ID checks | No account; connect a wallet | Account with ID checks |
| Dollars in and out | Yes: bank transfer or card | Rarely; mostly crypto-for-crypto | Yes, often the easiest |
| Can you withdraw coins? | Usually yes | They never leave your wallet | Depends on the app; some only let you hold them inside it |
| Typical costs | Trading fee plus spread; lower on the "advanced" screen | Pool fee plus network (gas) fee plus price impact | Spread and sometimes a flat fee; often the priciest per trade |
| What can go wrong | The company fails, freezes withdrawals or is hacked | Contract bugs, fake tokens, harmful approvals, fake front-ends | The company fails; poor prices; you can't move coins out |
For the basics of what any exchange does, see what is a crypto exchange? This guide goes deeper into how the three models differ.
How a centralized exchange works
When you deposit dollars or coins, the exchange records a balance for you in its own database. Your trades just move numbers between customers' balances; nothing touches the blockchain until you withdraw. That's why a CEX can be fast and cheap per trade, and why it can offer things a blockchain can't easily do, like card payments, customer support and password resets.
The cost is custody risk. Your balance is a promise from the company. When FTX collapsed in November 2022, customers found that their deposits had been moved to a related trading firm; the SEC's complaint said customer money was used for venture investments, property and political donations. Regulated exchanges must keep customer assets separate and check identities, and some publish proof-of-reserves reports, but none of that is the same as deposit insurance.
How a decentralized exchange works
A DEX has no company account. You connect a self-custody wallet such as MetaMask, choose two tokens, and sign a transaction that calls the DEX's smart contracts. Most DEXs use a liquidity pool: a contract holding two tokens, supplied by people who earn a share of the fees. A formula sets the price from the ratio of tokens in the pool, so bigger trades move the price more ("price impact").
What you pay on a DEX:
- The pool fee, a percentage set by the pool (commonly somewhere between 0.01% and 1%), paid to the liquidity providers.
- The network fee for your transaction, paid to the blockchain's validators. It can be cents on a layer 2 and much more on a busy Ethereum mainnet. See transaction fees.
- Price impact and slippage: the gap between the quoted and final price. Your wallet lets you set a maximum; set it tight.
- Sometimes a front-end fee charged by the website or app you use to reach the contracts.
There's no one to call if something goes wrong. Anyone can create a token with any name, so a "USDC" in a pool may be a fake; check the contract address on the issuer's own site. And approving a malicious contract can let it drain your wallet later. Read before you send crypto.
Brokers vs. exchanges
A broker sells to you directly at a quoted price instead of matching you with other traders. Many payment apps and stock-trading apps work this way for crypto. The price includes a spread, which can be wider than an exchange's fee, though the app may show "no commission". Some brokers let you withdraw coins to your own wallet; others only let you hold them inside the app, which means you can't use them elsewhere and depend fully on that company.
Many exchanges also have a broker-style "buy" or "convert" button. It's the same idea: convenient, with the cost built into the price. The "advanced" or "trade" screen on the same exchange usually costs less. Compare them with the true cost calculator.
A spot Bitcoin ETF bought in a brokerage account is different again: you own fund shares, not coins.
How the options compare in common situations
- Turning dollars into your first crypto: a regulated CEX or a broker that allows withdrawals. A DEX can't take your bank transfer.
- Holding long term: buy on a CEX or broker, then consider moving coins to a wallet you control. See custodial vs. non-custodial.
- Swapping tokens that already sit in your own wallet: a DEX avoids sending them to a company first, but you carry all the checking.
- Simplicity above all: a broker, accepting a higher cost and less control.
Whatever you use, type the address yourself. Fake exchange sites and copies of DEX front-ends are a common scam; see fake crypto trading sites.
Rules and protections
In the US, centralized exchanges and brokers that hold customer money generally register with FinCEN as money services businesses and hold state licenses, and they must verify identities. A DEX's contracts don't check ID, but the companies running popular front-ends often block sanctioned addresses or certain countries. None of the three gives crypto FDIC deposit insurance. If a CEX or broker goes bankrupt, customers can end up as creditors waiting years for partial repayment.
Related reading: Automated market makers and liquidity pools: how x · y = k works · What is MEV? Transaction ordering explained · Exchange security and proof of reserves · How crypto markets work · Phishing and wallet drainers
Frequently asked questions
Is a DEX safer than a CEX?
Neither is simply safer. A DEX removes the risk of a company losing or freezing your funds, but adds smart-contract bugs, fake tokens and the chance of signing something harmful, with no support desk. A regulated CEX adds company risk but helps with mistakes and account recovery.
Do I need ID to use a decentralized exchange?
The contracts themselves don't ask for ID. You usually need crypto in a self-custody wallet first, which most people get from an exchange that did check ID. Some DEX websites block certain regions or addresses.
What's the difference between a crypto broker and an exchange?
An exchange matches buyers with sellers and charges a fee; a broker sells to you at its own quoted price, with its margin built into that price. Some brokers don't let you withdraw coins.
Why did my DEX swap cost more than the quote?
Price impact, slippage while your transaction waited, the pool fee and the network fee. Check the minimum amount you'll receive before you sign.
Can a DEX freeze my funds?
The pool contracts generally can't touch tokens in your wallet. But a token's own issuer may be able to freeze it (stablecoin issuers can), and approvals you've signed can let a contract move tokens.
Are CEX vs DEX fees very different?
On a busy Ethereum mainnet a small DEX swap can cost more in network fees than the trade is worth. On a layer 2 or for larger trades a DEX can be competitive. A CEX's advanced screen is often cheapest for small dollar trades.
Where to next
Sources
- SEC charges Samuel Bankman-Fried with defrauding investors in FTX (SEC, December 13, 2022)
- Decentralized exchanges and DeFi (ethereum.org)
- Money services business registration (FinCEN)
- Crypto assets (Investor.gov, SEC)
Written for beginners and checked against the sources listed. Last reviewed November 4, 2026. This page is educational and is not financial, tax or legal advice. How we write and check pages.