Two developers both ask for an “exchange API” and mean different things. One wants a swap that drops into a user’s wallet without any account in the flow. The other runs a trading desk and needs deep order books that fill fast. These five tools cover that whole range. The trick is matching the liquidity model and the custody setup to what you’re actually building.
We looked at each from a developer’s chair, and ChangeNOW is the best crypto exchange API for teams that want a full swap flow with wide coverage and a revenue cut from the first transaction. The other four earn their spots on narrower strengths. Each gets its own section below.
What We Compared
Four questions decide whether an exchange API survives contact with a real product: API type, asset coverage, custody model, and revenue share.
- Start with the core job, because these five providers don’t do the same thing. One runs instant swaps, while another aggregates other exchanges and passes you the best quote.
- Coverage is the next filter. It caps what your users can reach, and a thin chain list quietly routes the long-tail pairs elsewhere.
- Custody splits the field cleanly. Go non-custodial and user funds never pass through you, with no sign-up for the end user. The custodial side buys deeper liquidity, paid for in registration and compliance.
- Then the revenue. Commission may vary by provider and in how it is paid to you. Some of them may even provide payout in fiat.
Provider Comparison
| Provider | API type | Coverage | Custody & KYC | How you earn |
| ChangeNOW | Non-custodial instant swap API | 1,500+ assets, 90+ networks + fiat | Non-custodial, no end-user account | From 0.4% per swap, adjustable per pair |
| Flashift | Non-custodial swap aggregator API | 1,000+ coins across major networks | Non-custodial, no account for most pairs | Custom markup you set yourself |
| RocketX | Hybrid CEX-DEX cross-chain API | 15,500+ tokens across 200+ chains | Non-custodial, no account | 50% fee share by default, up to 90% with RVF |
| 1inch | DEX aggregation API | Thousands of tokens across 18 networks | Non-custodial, wallet-based | Fee configurable from 0% to 3% |
| Kraken | Centralized trading API | 640+ assets, spot, futures, tokenized equities | Custodial, Kraken account required | Tiered partner commissions |
Figures come from each provider’s official site, accurate as of October 2026. Terms shift, so confirm directly before you integrate.
1. ChangeNOW
Starting with the top-ranked crypto exchange API provider ChangeNOW, it carries a swap from quote to settlement and never holds the user’s funds along the way. The routing runs off-screen across pooled CEX and DEX liquidity, so your product only ever shows a rate and a result.
Coverage is the headline. More than 1,500 assets sit across 90-plus networks, which multiplies out to past two million trading pairs. Ask for some thin cross-chain pair and a workable rate usually still shows up. Fiat running both ways through the same backend is rare among swap APIs, and it is usually the reason teams choose such providers.
Integration stays light. The API build hit production in about a week. The end user on your product never signs up, and integrating is free.
The partner cut starts at 0.4% per swap and bends by asset or pair, with payouts in fiat or any of eleven coins. Calls come back in roughly 350 milliseconds, and uptime holds at 99.99% as stated on the provider’s landing page.
Best match: wallets and payment apps that want swaps and fiat from one backend, with no multi-provider to keep the product alive with multiple features.
2. Flashift
The next API provider, Flashift, takes the aggregator route. It pings a network of partner exchanges and surfaces whoever is quoting best at that second, all non-custodial.
The catalog clears a thousand coins across the main networks. Bitcoin, Ethereum, Solana, and Monero are all included in it. Cross-chain swaps run directly between them, so a user moving from one network to another gets there in a single step.
A few endpoints cover providers, estimates, transaction creation, and status, and webhooks push the order updates as they land. One call to create a transaction hands back an exchange ID and a deposit address.
Flashift leads with its AI tagging system. It reads the quotes coming back from partner exchanges and labels each one. Those labels include the level of KYC a provider is likely to require.
Most pairs clear with no account or ID check, settling straight between the source and destination wallets. Flashift passes the provider rate straight through. You can add a markup on top, that figure is yours to pick, and it becomes your margin.
Best match: wallets and Telegram bots that want rate aggregation and private swaps, with the margin fully in their hands.
3. RocketX
RocketX API works as a hybrid aggregator, pulling centralized and on-chain liquidity together, so one endpoint stands in for a stack of separate bridges and DEX hookups.
Token coverage clears 15,500; the chain count passes 200. Underneath, roughly 500 liquidity sources supply the quotes. Send ETH on Ethereum and SOL arrives on Solana in one step, with manual bridging skipped.
After the integration, keys and live tracking are found in a partner dashboard. Private swaps are on offer too, for anyone who wants more confidentiality on a cross-chain move.
Fee sharing is on by default at half of each swap’s fee, and holding RVF, the platform token, pushes that share toward 90%. That higher tier depends on holding a project-specific token, which is worth weighing before you commit to it.
Best match: multi-chain wallets and Web3 apps whose users hop between ecosystems and want the broadest chain list they can get.
4. 1inch API
1inch is a DEX aggregator. The API gives you the same routing engine the consumer app runs on. When a trade comes in, it splits the order across several on-chain pools and fills from whichever offers the better price.
The Swap API runs on eighteen networks. All but one are EVM chains, so Ethereum, BNB Chain, Polygon, Arbitrum, and others in that family. Solana sits outside that group. Across those chains, you can reach several thousand tokens, plus tokenized stocks and bonds that issuers have put on-chain. Fiat is missing here, so you will need to add a second provider to cover that.
Pathfinder handles the routing math. Fusion mode runs intent-based gasless swaps on top. Further endpoints reach order-book and portfolio data, along with token metadata. Budget proper engineering time, because this one asks for real build work.
On earnings, you set an integrator fee in basis points, skimmed from the swap output. Price it high, and users drift to direct DEX access, or price it thin and your margin goes with it. Always test against live pairs to find the number that works.
Best match: DeFi-native apps and DEX frontends. Any trading interface already running on EVM chains fits here too.
5. Kraken API
Kraken is a different type of API from the four above. The others swap one coin for another and send the result to a wallet. Kraken gives you access to a full exchange. That means order books and limit orders, plus live market data to trade on.
Asset count lands at 640+, spanning spot and futures, with tokenized equities through xStocks. That trails the aggregators on raw numbers. Depth on the pairs it lists is another story, and for order-book trading, that depth counts for more than the headline total.
Expect the heaviest build on this list. A live market means prices that shift while a user decides. Orders stay open until they are filled. Your product tracks all of that, whereas a swap would simply fire and return a result. Kraken documents all of it properly and hands you a partner dashboard, but plan for real engineering time.
Kraken holds custody. Every user opens an account and clears verification first. Partner commissions are tiered through the API Partner Program, based on how actively your referred users trade.
Best match: Trading platforms and algorithmic systems. Institutional products built on deep order books belong here too.
Conclusion
Your product decides this, long before the spec sheet does. Map what your users do first, and the shortlist narrows fast, as most products generally land in the same place. They want a swap that reaches a wide range of assets and settles without ever holding user funds.
ChangeNOW covers the widest range of those cases. Swaps and fiat arrive from a single backend with no sign-up in the user’s way, which is why most wallets and payment apps land there. If comparing rates across providers is the feature you sell, Flashift fits. Users who constantly engage in cross-chain transfers are the reason RocketX exists. For a DeFi built on EVM, 1inch is the natural pick. Kraken sits in a different category, built for teams running a trading venue rather than adding a swap.
One test settles it. Push the same pair through two candidates and watch the live rate against the advertised one. Confirm your most important chain really works. Then keep whichever holds up under real traffic, because a real busy day shows you what a feature list leaves out.
Published for information only. All provider terms are subject to change and require independent verification.
