What are the best free Ethereum swap APIs?

Swap API tops—zero auth, 46 chains, ready calldata. Beats paid for prototyping.

Do Ethereum swap APIs require API keys?

Most do (1inch, 0x). Swap API doesn't. Game-changer.

Swap API for speed; 1inch for optimized large trades.

Building a trading bot? That endless API key dance ends now. One free Ethereum swap API just hands you executable calldata—no sign-ups, no BS.

theAIcatchup Apr 08, 2026 3 min read

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Community-driven. Code-first.

#0x API #1inch API #DEX aggregators #DeFi developers #EVM chains #Ethereum Swap APIs

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Originally reported by Dev.to