How to check which tokens you can swap through 0x API

Last updated: June 25, 2026

A common question from integrators is "where's the list of supported tokens?" The short answer: there isn't a fixed list, and you don't need one. This article explains how token availability actually works on 0x and how to check whether a specific token can be traded.

0x supports tokens by default

0x supports all tokens by default, except for tokens blocked for compliance reasons. Because 0x aggregates liquidity across many sources, any ERC-20 token that has liquidity on one of those sources can generally be traded — including buy/sell tax (fee-on-transfer) tokens.

This means token availability isn't really a question of "is it on a list." It's a question of "does this token have liquidity that 0x can route through." So instead of fetching a master token list, the right way to check availability is to ask the API for a price or quote on the specific token you care about.

How to check if a specific token can be traded

To confirm a token is swappable, request an indicative price (or a firm quote) for the pair you want, specifying the token's contract address and the chain. The response tells you what you need to know:

  • If 0x can route the trade, you'll get back a price/quote with the route and expected amounts.

  • If there's no viable liquidity, the API indicates that liquidity isn't available rather than returning a fillable quote — your signal that the token can't currently be swapped at that size on that chain.

In other words, the price/quote endpoints double as your availability check. For the exact endpoints, parameters, and the field that indicates whether liquidity was found, see the 0x API reference.

What about a custom token or a brand-new altcoin?

If a token can't be swapped, it's almost always because it doesn't yet have liquidity that 0x's sources can reach. To trade a custom token, you first need to create liquidity for it — for example, by creating a liquidity pool for the token on one of the AMM sources 0x aggregates from, such as Uniswap, SushiSwap, or Curve. Once that liquidity exists, 0x can route to it.

Which liquidity sources are available on a chain?

Token availability depends on the liquidity sources active on a given chain. If you want to see those sources, use the dedicated sources endpoints — see the help-center article on finding 0x Swap API liquidity sources for each chain, or go straight to the getSources reference.

Key takeaways

  • There's no fixed "supported tokens" list to download — 0x supports tokens by default, minus compliance-blocked ones.

  • Check availability by requesting a price or quote for the specific token and chain; the response tells you whether liquidity is available.

  • A token that can't be traded usually just needs liquidity created on a supported source first.

  • You'll need a free 0x API key to make these requests.