Immediate UI mode for logins

Eiji Kitamura
José Luis Zapata

Published: May 12, 2026

Immediate UI mode for logins is a web capability designed to streamline sign-in flows. This feature lets you proactively offer passkeys and managed passwords directly to your users when they reach a sign-in moment, such as clicking a Sign In or Checkout button.

Abstract

Immediate UI mode provides a mode that fails promptly if no credentials are locally available. This behavior mirrors preferImmediatelyAvailableCredentials APIs found on mobile platforms like Android and iOS. When credentials exist, the browser presents an immediate login dialog to the user. Otherwise, it rejects the promise silently, letting you provide alternative sign-in methods, for example, a sign-in form, without disrupting the user experience.

As of May 2026, Chrome is the only browser that supports immediate UI mode.

Check prerequisites

To use immediate UI mode, the user must already have eligible credentials available locally on their device. On Chrome, these credentials include:

  • Passkeys saved in a passkey provider such as Google Password Manager, Windows Hello, or iCloud Keychain.
  • Passwords saved in Google Password Manager.

If no local credentials exist, the API rejects the request without showing the immediate login dialog.

Detect feature support

Before you call immediate UI mode, verify whether the browser supports the immediateGet capability using the PublicKeyCredential.getClientCapabilities() method. If it is not supported, fall back to existing sign-in methods, such as email and password forms, phone number verification, or social logins.

async function checkImmediateAvailability() {
  try {
    const capabilities = await PublicKeyCredential.getClientCapabilities();
    if (capabilities.immediateGet) {
      console.log("Immediate UI mode is supported.");
    } else {
      console.log("Immediate UI mode is NOT supported.");
    }
  } catch (error) {
    console.error("Error checking client capabilities:", error);
  }
}

For broader browser support, use the polyfill available in the WebAuthn Polyfills GitHub repository.

Request credentials

To trigger the immediate login flow, call navigator.credentials.get() with the uiMode field set to 'immediate'.

By including password: true in your request, users can benefit from this experience if the browser supports password credentials.

// This call must follow a user gesture, like a button click
button.addEventListener('click', async (event) => {
  event.preventDefault();
  try {
    const cred = await navigator.credentials.get({
      password: true,
      publicKey: {
        challenge: serverGeneratedChallenge,
        rpId: 'example.com'
      },
      uiMode: 'immediate',
    });
    // Handle successful sign-in
  } catch (error) {
    if (error.name === 'NotAllowedError') {
      // Provide a fallback sign-in experience
      showFallbackUI();
    }
  }
});

You must handle the NotAllowedError in a catch block to provide a fallback sign-in experience.

Handle sign-in flows

You can implement immediate UI mode for two primary scenarios.

Sign in with a button

Provide a dedicated sign-in button that offers a clean experience without unexpected prompts.

  1. The user clicks a Sign in button.
  2. Your site calls navigator.credentials.get() with uiMode: "immediate".
  3. The browser checks for local credentials.
  4. If the browser finds credentials, it presents an immediate login dialog for the user to select an account.
  5. If the browser finds no credentials or the user dismisses the immediate login dialog, it throws a NotAllowedError.
  6. If a NotAllowedError is thrown, your site then proceeds with its standard sign-in page.

Sign in before a checkout

Offer credentials proactively before a user performs an action that would benefit from authentication, such as starting a checkout flow at an online storefront.

In ecommerce, guest users often select between signing in to an existing account or checking out as a guest. Providing an immediate login dialog can streamline the checkout process for returning customers.

  1. The user initiates an action, such as clicking a Checkout button during a shopping flow.
  2. Your site calls navigator.credentials.get() with uiMode: "immediate".
  3. If credentials exist, the user selects one to complete the sign-in.
  4. If credentials don't exist, the browser throws an error and shows no immediate login dialog. The user experience remains unchanged, and you can take the user to the existing checkout screen, which might provide other sign-in options or a guest checkout form.

Review privacy and security measures

The browser implements critical measures to protect user privacy:

  • User gesture requirement: You must initiate the API call with a user gesture, such as a click, to prevent silent probing. The call does not consume the activation.
  • Incognito mode restrictions: Requests in incognito or private sessions always throw a NotAllowedError.
  • No allowlists: Requests with a non-empty allowCredentials list throw a NotAllowedError to prevent cross-session tracking.
  • No programmatic cancellation: You cannot use the signal parameter to programmatically dismiss the immediate login dialog.