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AuthenticatorAssertionResponse: authenticatorData property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨September 2021⁩.

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The authenticatorData property of the AuthenticatorAssertionResponse interface returns an ArrayBuffer containing information from the authenticator such as the Relying Party ID Hash (rpIdHash), a signature counter, test of user presence, user verification flags, and any extensions processed by the authenticator.

Value

An ArrayBuffer with a ArrayBuffer.byteLength of at least 37 bytes, which contains the data structure explained in Authenticator data.

Examples

See Retrieving a public key credential for a detailed example.

Specifications

Specification
Web Authentication: An API for accessing Public Key Credentials - Level 3> # dom-authenticatorassertionresponse-authenticatordata>

Browser compatibility

	Desktop					Mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	WebView on iOS
`authenticatorData`	67	18	60 Only supports USB U2F tokens.	54	13	70	92 60–92 Only supports USB U2F tokens.	48	13	10.0	No	13

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https://developer.mozilla.org/en-US/docs/Web/API/AuthenticatorAssertionResponse/authenticatorData