How to find the 0x API (Swap & Cross-Chain) liquidity sources for each chain

Last updated: June 25, 2026

0x aggregates liquidity from many sources, and which sources are available varies by chain. If you want to see the full list of liquidity sources 0x supports on a given chain — for example, to display them to your users, to understand where a quote's liquidity comes from, or to exclude specific sources in your requests — the API exposes a dedicated endpoint for it.

This article explains what's available at a conceptual level. For the exact request format, headers, and response schema, use the canonical API reference linked in each section.

EVM chains: the Sources endpoint

For EVM chains, the getSources endpoint returns the array of liquidity sources 0x aggregates for a specific chain. You tell it which chain you want using a chainId parameter, and it returns the list of source names available there (AMMs and other venues, including 0x's exclusive RFQ liquidity).

You can find the full reference — including required headers and an example response — here: getSources API reference. For the list of chain IDs to query, see Supported Chains.

Cross-Chain API: the listSources endpoint

The Cross-Chain API has its own sources endpoint, listSources, because a cross-chain swap involves two different kinds of liquidity. It returns:

  • Bridge providers — the bridges available and which origin/destination chain pairs each one supports.

  • Swap sources — the on-chain liquidity sources available, along with the chains each one covers.

This lets you see both how tokens can move between chains and where they can be swapped on each side. The full reference is here: Cross-Chain listSources API reference.

Which one should I use?

Use getSources when you're working with single-chain swaps on an EVM chain (0x Swap API). Use the Cross-Chain listSources endpoint when you're building cross-chain swaps (0x Cross-Chain API) and need to know the available bridges and per-chain swap sources. Both require a 0x API key, which you can create for free on the 0x Dashboard.

Where to go next

For the exact endpoints, parameters, headers, and response shapes, always defer to the API reference: