A DEX, or decentralized exchange, lets you swap tokens directly from your own wallet through smart contracts, with no company holding your funds and no account to open. You keep your keys throughout.
Volume is substantial and still smaller than the centralized side. In June 2026, DEX trading across all chains reached $7.2 billion in a single 24-hour period. Uniswap accounted for roughly 27% of it.
How a DEX works
No order book in most cases. A formula instead.
You connect a wallet, choose two tokens, and confirm a swap. Execution happens against a liquidity pool, which is a smart contract holding reserves of both tokens deposited by other users. From the ratio between those reserves comes the price.
Four steps, and none of them involve an intermediary holding your assets.
- Connect a wallet. No sign-up, no email, no verification.
- Approve the token for spending by the contract.
- Submit the swap, paying a network gas fee.
- Receive the tokens directly to your wallet.
That approval step in the middle is where a lot of people get hurt. Granting a contract permission to spend your tokens creates a standing authorisation. Malicious contracts exploit exactly this.
The main designs
| Type | How it prices trades | Examples |
|---|---|---|
| AMM | Formula against pooled reserves | Uniswap, PancakeSwap |
| Stableswap AMM | Curve tuned for assets near parity | Curve |
| Concentrated liquidity | Providers choose a price range to supply within | Uniswap v3 and later |
| Aggregator | Routes your trade across several venues for the best price | 1inch, Jupiter |
| Order book DEX | Matching engine off-chain, settlement on-chain | Various newer platforms |
Most volume runs through AMMs. Fully on-chain order books remain rare, since posting and cancelling orders costs gas every time.
DEX vs CEX
| DEX | CEX | |
|---|---|---|
| Who holds your keys | You | The exchange |
| Identity verification | Generally none | Required |
| Fiat deposits | Rarely, usually via a third party | Yes |
| Token selection | Anything anyone lists, instantly | Reviewed before listing |
| Order types | Swap only, generally | Market, limit, stop |
| Account recovery | None | Possible through support |
| Main risk | Smart contract exploits, user error | Platform failure |
Neither is safer in the abstract. Carrying insolvency risk, a centralized exchange at least offers recourse. A DEX removes custody risk and offers none.
What a DEX is genuinely good for
- New tokens. Anything can be listed the moment it exists, long before a regulated venue reviews it.
- Self-custody throughout. Funds never leave your wallet except during the swap itself.
- No permission required. No account approval, no geographic restriction at the protocol level.
- Composability. A DEX plugs into lending protocols and aggregators without any partnership.
- Transparency. Every trade, pool balance, and fee is publicly verifiable on-chain.
The risks
Smart contract risk. Code holds the funds. Bugs and exploits can drain a pool, which has happened repeatedly across DeFi.
Token approvals. Permission granted to swap can be unlimited and permanent unless revoked. Wallet drainers rely on it.
No recourse. Sending to the wrong contract, approving a malicious one, or mistyping an amount leaves you with no support desk.
Slippage on thin pools. Pool depth determines your price. Against a small pool, a large trade moves it sharply against you.
MEV. Watching pending transactions, bots can front-run or sandwich yours, extracting value before it settles.
Unvetted listings. Openness that lists a good token instantly lists a honeypot just as fast. Roughly 93% of 388,000 Solana pools examined by Solidus Labs showed soft rug pull characteristics.
Gas costs. On a busy network, small trades can cost more in fees than the trade is worth.
Where mb.io fits
Removing the intermediary also removes everything the intermediary provides. Which trade suits you depends on what you are trading and how much recourse you want.
mb.io is a regulated crypto spot exchange backed by MultiBank Group, a financial institution founded in 2005 that serves more than 2 million clients across 100+ countries.
- Regulated by VARA in the UAE and AUSTRAC in Australia
- 10/10 security score from Hacken, an independent blockchain security auditor
- Institutional-grade MPC custody powered by Fireblocks, with segregated client funds
- Every listed asset is reviewed before it reaches the platform
- Buy, sell, and swap in three steps, from sign-up to purchase
- 24/7 customer support, on web and on the iOS and Android apps
Open your account and start trading on mb.io.
Frequently asked questions
What does DEX stand for?
Decentralized exchange. It refers to a trading platform running on smart contracts, where users swap tokens from their own wallets without a company holding funds.
Do I need KYC to use a DEX?
Generally not, since there is no company to onboard you. Regulators have been extending obligations toward interfaces and developers, and the position varies by jurisdiction.
Is a DEX safer than a centralized exchange?
Custody risk goes, and smart contract risk, approval risk, and zero recourse arrive. Different risks rather than fewer.
Why did my DEX trade cost more than the quote?
Slippage, MEV, or both. As your trade executes the pool price moves, and bots can sequence transactions around yours to extract value.
What is a token approval and why does it matter?
Permission for a contract to spend tokens from your wallet. Unlimited and persistent until revoked, approvals are the mechanism most wallet drainers exploit.
Can I buy crypto with a bank card on a DEX?
Not directly. Fiat entry generally requires a regulated entity with banking relationships, which is why most people start on a crypto exchange and move funds on-chain afterwards.
What is the largest DEX?
By volume, Uniswap, accounting for roughly 27% of all DEX trading in June 2026 across its v2, v3, and v4 deployments.
Are DEX listings vetted?
No. At any time, anyone can create a pool for any token. That openness is the main appeal and the main risk.
