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API
WhatsUsernames.link's public REST API for generating links, validating usernames, and creating QR codes programmatically.
A free API, no key or signup required, with CORS enabled. Includes the whatsusernames-sdk, a dependency-free TypeScript/JavaScript client for the public endpoints (links, QR codes, BSUID, Business Platform webhooks).
Last updated July 5, 2026
Frequently asked questions
Do I need an API key?
No — the API is open and free, with no key or registration required.
Is there a rate limit?
Yes, a reasonable rate limit applies to keep the free API usable for everyone — see the developers page for current limits.