CEX vs perp DEX arbitrage: differences and risks
A perp DEX is a decentralized exchange for perpetual futures: trades go through smart contracts or a dedicated blockchain, and funds stay with the user in a wallet or in the protocol’s deposit. Such venues are interesting for arbitrage because their rates and prices often differ from centralized exchanges (CEX) more than prices differ between CEXes themselves.
What is the same as CEX–CEX arbitrage
The logic is the same: two legs, one asset, different prices or funding rates. Everything said in the guides on the cross-exchange spread and funding arbitrage applies here too. What changes are the execution details and the set of risks.
The main differences
| Parameter | CEX | Perp DEX |
|---|---|---|
| Custody of funds | On the exchange, with its custodian | In your wallet or the protocol’s contract; you hold the keys |
| Onboarding | Registration, usually KYC | Connecting a wallet; requirements depend on the venue |
| Collateral | Usually USDT | Usually USDC or the protocol’s own stablecoin |
| Funding interval | Usually 8 hours, sometimes 4 or 1 | Often every hour |
| Liquidity | Deep books on large exchanges | Many venues have thinner books, especially for small coins |
| Fees | Taker/maker by account tier | Their own scheme: zero fees or rebates exist, gas may be charged |
| Venue risk | Counterparty, withdrawal freeze | Smart contract, oracle, network or sequencer failure |
What to consider in practice
- Funding interval. If the DEX rate is hourly and the CEX rate is every 8 hours, compare them after bringing them to one period (see the funding rate guide). Payments arrive at different times, so over different holding times a pair gets a different number of payments.
- Collateral in different currencies. If one venue holds USDT collateral and the other USDC, there is a small extra risk of the exchange rate between them drifting.
- Deposits and withdrawals. Moving funds between a CEX and a DEX goes through a network; the fee, speed and availability depend on the network chosen. Do not leave margin skewed to one leg.
- Limits and liquidity. Check position size, open interest and order-book depth on both legs, especially for small coins.
- Liquidation. The margin model and liquidation price on a DEX may differ from a CEX, and liquidation runs by the protocol’s rules. Leave a bigger reserve.
- Technical failures. A network halt, an oracle delay or overload are events that happen less often on a CEX or behave differently there.
Who it suits
This scheme suits those who are ready to manage two kinds of infrastructure at once — an exchange account and a wallet — and understand smart-contract risks. If you are only learning arbitrage, it is easier to start with CEX–CEX pairs and add DEXes later. See also the risk checklist.
How it works in SpreadScope
The scanner shows pairs between CEXes, between perp DEXes and mixed CEX ⇄ perp DEX pairs; the exchange list can be limited with a filter. The subscriptions are named accordingly: CEX opens pairs between centralized exchanges, DEX — between perp DEXes (plus the DEX pool scanner against CEX futures), and both together — all pairs, including mixed ones. Rates are brought to one period, and for most perp DEXes quotes and order books come over WebSocket, so data in the table and on the chart updates almost immediately.