What the passkey support checker actually asks
Press the button and the page asks this browser four small questions. Is the Web Authentication API present? Can the browser see a built-in, user-verifying authenticator? Does it expose conditional mediation, the feature behind some passkey suggestions in sign-in fields? Finally, if WebAuthn exists, the page explains that a compatible external security key may work even though a browser cannot inventory every key sitting in a drawer.
No credential is created. There is no fingerprint reading, device scan, or account lookup. The browser returns capability answers defined by WebAuthn, and the page translates them. That distinction matters when a result says “not reported as available.” It may describe this browser tab, not the whole phone or computer. An embedded browser inside a mail or social app can answer differently from the full browser installed on the same device.
A concrete browser and device example
On Safari on a current Mac with Touch ID configured, a common result is WebAuthn available and a built-in platform authenticator available. Conditional sign-in may also be available, depending on the Safari and macOS versions and local settings. The same Mac opened through an embedded web view can lose one of those capability signals. The hardware did not change; the software surface answering the question did.
Chrome on an Android phone with a screen lock offers another useful comparison. WebAuthn and the platform authenticator are commonly reported, while the website still decides whether it offers passkeys to that account. A managed work profile, an outdated browser, or a disabled credential provider can change the answer. Run the test where you plan to sign in. If a result surprises you, update the browser and operating system, confirm a screen lock is active, and leave the in-app browser for the full one.
Built-in authenticators are not external keys
A platform authenticator lives with the phone or computer and normally asks for the device unlock: Touch ID, Face ID, Windows Hello, an Android screen lock, or a device PIN. A roaming authenticator is separate hardware—a FIDO security key connected over USB or tapped with NFC, for example. Both speak WebAuthn, but the platform-availability method only answers the built-in question.
That is why “platform authenticator unavailable” does not automatically rule out a security key. If WebAuthn itself is available, a service may still offer an external key during enrollment. The checker cannot safely wake, probe, or list keys that have not been attached. It also cannot say where a passkey would sync. Credential-provider settings, operating-system policy, and the service’s own enrollment choices decide that later.
Use the result before changing a real account
A row of positive answers means the browser has useful building blocks. It does not mean GitHub, LinkedIn, or another named service has enabled passkeys for your account, region, or organization. Check the service directory, then begin enrollment only from the verified official domain. If the account is controlled by an employer, the administrator may choose the available credential provider or require a different method.
Keep the old sign-in route until the new one survives a real test. Enroll the passkey, open a private window, and sign in again while the original trusted session remains available. Then review recovery contacts and any backup method. Passkeys resist many lookalike-domain attacks because credentials are scoped to a relying party, but they do not repair a stolen unlocked session, a malicious connected app, or a weak recovery process. The capability check is the start of that work, not the finish.
Practical sequence
How to use this tool safely
- 01
Select Run the passkey support check in the browser and device you intend to use.
- 02
Review WebAuthn, built-in authenticator, and conditional sign-in as separate results.
- 03
Compare the device result with the target service’s documented passkey record.
- 04
Keep an independent recovery route before replacing an existing sign-in method.
Common questions
Passkey support checker FAQ
Does a positive check mean every website supports passkeys?
No. The check reports browser and device capabilities. Each website decides whether passkeys are available and can limit them by account, platform, region, or organizational policy.
Can a security key work if the platform check says no?
Possibly. The platform test concerns a built-in user-verifying authenticator. A compatible external FIDO security key may still work when WebAuthn is available, but this page cannot detect every unattached key in advance.
Why does the result differ between browsers?
Browsers can use different operating-system integrations, versions, permissions, and embedded-view restrictions. Test the full, updated browser you expect to use for the real account.
Does this test create a passkey?
No. It only asks the browser about capability. Use the separate passkey demo if you want to experience a local create-and-use ceremony without creating an account.
References