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send21

Crypto pay links and API for people and AI agents: non-custodial BTC, Lightning, USDC, USDT, EURC, SOL and ETH payment requests

CryptocurrencyAuth: API KeyHTTPS: YesCORS: noStatus: alive

Last verified: November 12, 2026

Reliability

100% uptime: the documentation responded in 5 of 5 checks over the last 30 days. Median response time: 426 ms.

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At a glance

  • Authentication: API Key
  • HTTPS: Yes
  • CORS: No, call it from a server
  • Documentation: https://send21.io
// Fetch the docs page with cURL curl https://send21.io

History

  • November 12, 2026: last health check, responding
  • November 2, 2026: Added to the directory (imported from marcelscruz)

See every change to the directory →

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