Ethereum's zkAPI Brings Private Payments to Mainnet

The Ethereum Foundation has announced that zkAPI, a system for private API payments, is now live on mainnet. Users can deposit funds into an Ethereum vault and use zero-knowledge proofs to prove they have enough credit without revealing their billing identities.

This allows users to pay for AI services without linking the payment to their identity. The system issues short-lived API keys with predefined spending limits, sending prompts directly to the AI provider while usage is settled separately through the payment layer.

The project has released a local client and software development kit, along with a browser-based AI chat implementation. This follows a February proposal by Ethereum Foundation researcher Davide Crapis and co-founder Vitalik Buterin for ZK-based API usage credits.