A CEX, or centralized exchange, is a crypto trading platform run by a company that holds your funds, matches your orders, and processes your deposits and withdrawals. Binance, Coinbase, and mb.io are all centralized exchanges.
Most crypto trading still happens on one. Decentralized exchanges handled roughly $7.2 billion in daily volume across all chains in June 2026, a fraction of what centralized platforms process, largely because a CEX is where fiat currency enters the system.
What "centralized" actually means
Custody and control are what the word describes, rather than the number of servers.
On a CEX, the company holds the private keys to the wallets containing your crypto. Your balance is a number in the company's database, and a trade between two users updates two database entries without touching a blockchain at all. Only deposits and withdrawals move funds on-chain.
Because of that design, trades settle instantly and cost nothing in gas. It is also why the phrase "not your keys, not your coins" exists.
How a CEX works
Four systems, running together.
- Onboarding. KYC verification establishes who you are before you can trade.
- Custody. Deposits go into wallets the exchange controls, typically split between cold storage held offline and hot wallets for withdrawals.
- Matching engine. Orders are paired against the order book by price and time priority.
- Settlement. Internal balances update instantly. The blockchain only sees activity when you withdraw.
CEX vs DEX
| CEX | DEX | |
|---|---|---|
| Who holds your keys | The exchange | You |
| Identity verification | Required | Generally none |
| Fiat deposits | Yes | Rarely, usually via a third party |
| Pricing | Order book | Liquidity pool formula |
| Order types | Market, limit, stop, and others | Swap only |
| Account recovery | Possible through support | None, ever |
| Main risk | Platform failure or insolvency | Smart contract exploit, user error |
| Regulation | Licensed in major jurisdictions | Largely outside existing frameworks |
Neither one is universally safer. They fail differently, and the failure modes are worth understanding before choosing.
Why people use a CEX
- Fiat on-ramps. Converting dollars, euros, or dirhams into crypto realistically requires a regulated entity with banking relationships.
- Deep liquidity. Major pairs on large exchanges absorb size with minimal slippage.
- Real order types. Limit orders and stop-loss orders exist on a CEX and generally not on an AMM.
- Recoverable accounts. Losing a password is an inconvenience rather than a permanent loss.
- Support. Someone exists to contact when a deposit does not arrive.
The risks
Custody risk, first and largest. Your assets are held by the platform. If it becomes insolvent, is hacked, or freezes withdrawals, your access depends entirely on its solvency and conduct. FTX ranked among the largest exchanges in the world before collapsing in November 2022, having commingled customer funds with company money.
Counterparty opacity. Without proof of reserves, you cannot independently verify that the exchange holds what it says it holds.
Regulatory and jurisdictional risk. An exchange operating outside a licensing framework can restrict or close your account with little recourse.
Data risk. Completing KYC means the platform holds your identity documents, and exchange data breaches have exposed customer information before.
How to assess one
- Named regulator and a verifiable licence on the authority's own public register.
- Segregated client funds, held separately from company money.
- Independent security audits, published rather than self-reported.
- Proof of reserves, ideally with an accompanying liabilities attestation.
- Withdrawal reliability, since delays are historically the earliest signal of trouble.
- A curated listing process, because thousands of listings usually means nobody reviewed them.
Where mb.io fits
As a regulated crypto spot exchange, mb.io is a CEX operating under supervision rather than outside it.
It is 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
- A curated list of assets, so you're not sorting through thousands of tokens to find the ones worth trading
- 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 CEX stand for?
Centralized exchange. It describes a crypto trading platform operated by a company that holds customer funds and matches orders internally, as opposed to a decentralized exchange running on smart contracts.
Is a CEX safer than a DEX?
They carry different risks rather than different amounts of risk. A CEX exposes you to platform insolvency and adds regulatory protection and account recovery. A DEX removes custody risk and adds smart contract risk with no recourse for mistakes.
Why do centralized exchanges require KYC?
Because anti-money laundering law requires it in every major jurisdiction. Licensed platforms must verify customer identity and monitor activity, which is a condition of holding the licence.
Do CEX trades happen on the blockchain?
No. Trades update the exchange's internal database, which is why they settle instantly and incur no gas fee. Only deposits and withdrawals move funds on-chain.
What is proof of reserves?
A published attestation that an exchange holds the assets it owes customers, usually verified cryptographically. Pairing it with a liabilities audit makes it stronger, since reserves alone do not show what is owed against them.
What happened to FTX?
FTX collapsed in November 2022 after customer funds were found to have been commingled with company money and used elsewhere. Since then it has served as the standard example of why custody arrangements and regulation matter.
Can a centralized exchange freeze my account?
Yes. Regulated platforms may freeze accounts to comply with sanctions screening, anti-money laundering obligations, or a court order. That authority is a consequence of operating inside a regulatory framework.
