Note: Credentials will expire after 24h
If you have registered a user, you can sign in by pressing Login button. For login operation Username field is required and you can change User Verification option
If during registration Yes option is selected for Register with Resident Key, you will be able to login without the need for username since credentials are stored on authenticator To login with Resident key press Resident Login button
To check if your authenticator is original Cryptnox device press Check Authenticity button In this case there is no need to enter Username
This free tool lets you test any FIDO2-certified security key or passkey directly in your browser using the WebAuthn API. No software installation is required — everything runs client-side. Here's how to get started:
Enter any username in the field above. This doesn't need to be a real account — it's purely for testing purposes. Choose your preferred configuration options (explained below), then click Register. Your browser will prompt you to interact with your security key — tap it, enter a PIN, or use biometrics depending on your device.
After successful registration, click Login to test the authentication flow. Enter the same username you registered with, then interact with your security key when prompted. A successful authentication confirms your key is working correctly with the WebAuthn protocol.
If you registered with the Resident Key option set to "Yes," you can test passwordless login by clicking Resident Login. This authenticates you without requiring a username — the credential is stored directly on your security key. This is the foundation of true passwordless authentication.
If you're using a Cryptnox FIDO2 security key card, click Check Authenticity to cryptographically verify that your card is a genuine Cryptnox device. This uses the card's embedded attestation certificate to confirm authenticity — no username required.
Attestation determines how much information your security key shares about itself during registration:
User verification adds a second factor at the authenticator level — typically a PIN, fingerprint, or face recognition:
A resident key is a FIDO2 credential stored directly on the authenticator rather than held by the server:
Not all authenticators support resident keys. Storage capacity varies — some FIDO2 keys can store 25+ resident credentials, while others support fewer. This tool lets you test whether your device supports resident key storage.
FIDO2 is an open authentication standard developed by the FIDO Alliance and the W3C that enables strong, passwordless authentication using public-key cryptography. It is composed of two complementary specifications:
Together, WebAuthn and CTAP2 form the complete FIDO2 framework. When a website supports FIDO2, you can register a hardware security key and then use it to log in without ever typing a password. The private key never leaves your authenticator, and each registration creates a unique key pair per service — eliminating the risks of password reuse, phishing, and credential theft.
Passkeys are an evolution of FIDO2 that extend the technology to platform authenticators (built into phones, laptops, and operating systems) and enable cross-device synchronization. Traditional FIDO2 security keys store credentials on the physical device only — if you lose the key, the credential is gone. Passkeys can be synced across devices through cloud services like iCloud Keychain or Google Password Manager. Both passkeys and FIDO2 hardware keys use the same WebAuthn protocol, which is why you can test both with this tool.
Testing your FIDO2 security key is important for several reasons:
This tool works with any FIDO2-certified authenticator that supports the WebAuthn protocol. This includes USB security keys (like YubiKey and Feitian), NFC security key cards (like Cryptnox FIDO2 cards), built-in platform authenticators (Windows Hello, Touch ID, Face ID), and passkeys synced through your operating system. If your browser supports WebAuthn, this tool will work with your authenticator.
Yes. All cryptographic operations run entirely in your browser using the WebAuthn API. Your private keys never leave your authenticator device. Test credentials are generated for this demo server only and expire after 24 hours. No personal data is collected or stored beyond the temporary test session.
WebAuthn is supported by all major modern browsers: Chrome (67+), Firefox (60+), Edge (18+), Safari (13+), and Opera (54+). Mobile browsers on Android (Chrome, Samsung Internet) and iOS (Safari 14+) also support WebAuthn. For the best testing experience, use the latest version of your browser.
Common reasons for failure include: your browser doesn't support the selected options (try setting Attestation to "None" and User Verification to "Discouraged"); your security key doesn't support resident keys (try setting Resident Key to "No"); a timeout occurred because the key wasn't tapped in time; the security key requires a PIN that hasn't been set up yet; or the key requires NFC and your device doesn't have an NFC reader — in that case, consider the Cryptnox Contactless Reader.
Cryptnox FIDO2 security key cards are credit-card-sized NFC smart cards that fit in your wallet. Unlike USB dongles, they connect wirelessly via NFC — simply tap the card to your phone or NFC reader to authenticate. They are FIDO2 Level 1 certified, support resident keys, and include a built-in authenticity verification feature you can test with the "Check Authenticity" button above. Learn more about Cryptnox FIDO2 cards →
Cryptnox manufactures NFC-based FIDO2 security key cards that combine the security of hardware authentication with the convenience of a credit-card form factor. Our FIDO2 cards support passwordless login, resident keys, and work with Microsoft 365, Google, GitHub, and any service that supports the FIDO2/WebAuthn standard.