Cross-Subdomain Lab

Test credential sharing between subdomains. Register here, authenticate from passkeys, and vice versa.

How Cross-Subdomain Testing Works

WebAuthn credentials are scoped by rpId. If you register with rpId = "" (the parent domain), the credential should be usable from any subdomain. If you register with rpId = "", it is locked to this subdomain.

To test the full matrix: register credentials on the passkeys subdomain with parent-domain rpId, then come here and attempt authentication.

Register Credential

RP ID

Username

Authenticate from Here

RP ID

Credential IDs (comma-separated or JSON, optional)

Cross-Site Matrix

No credentials found. Register some credentials above or on the passkeys subdomain.

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