Is there an alternative to Google One Tap?

Google One Tap is the small prompt that offers “Continue as Jane” with a Google account, right on your page. It is quick for visitors who are signed in to Google. But it only ever offers Google accounts, and every sign-in goes through Google.

If you want one-tap sign-in without those limits, you have options. The browser API under One Tap works with other identity providers, passkeys give returning users their own one-tap sign-in, and some hosted providers ship a “Continue as” prompt of their own.

What is Google One Tap?#

Google One Tap is one part of Sign in with Google, which Google ships as the Google Identity Services (GIS) JavaScript library. When a visitor is signed in to Google in their browser, the library offers their Google accounts in a small prompt. One tap hands your page, or your login endpoint, a Google ID token: a signed JWT that your server must check (signature, aud, iss and exp) before it trusts it.

In Chrome, One Tap runs on FedCM (Federated Credential Management), a browser API for sign-in prompts. Google started moving One Tap onto FedCM in 2024, and the old use_fedcm_for_prompt opt-in is now deprecated and ignored. Chrome draws the prompt itself, so it no longer needs third-party cookies. Google’s FedCM migration guide lists what changed for sites.

Other browsers get less. Google’s docs say the normal One Tap prompt doesn’t work in Safari, Firefox or Chrome on iOS. With itp_support turned on, those browsers show a welcome prompt that opens a popup window, and automatic sign-in isn’t supported there. Where it is supported, auto_select signs a returning visitor in without a tap when exactly one Google session has approved your app before.

Why look for an alternative?#

Google One Tap does its job well. The reasons to look elsewhere are about the accounts, not the prompt:

• Only Google accounts. People without a Google account, or who don’t want to use it on your site, need another way in. You build a second sign-in anyway.
• Google is part of every sign-in. An identity provider always learns when someone signs in to a site with it, because it issues the token. FedCM stops Google from linking a visit to a Google account before the person continues, but each sign-in still goes through Google.
• The account belongs to Google. Your user’s identity is their Google account. If they lose access to it, they lose that way in, and moving people to another sign-in later means linking accounts yourself.
• Google and Chrome decide when the prompt shows. On desktop you can’t position it. After someone closes it, Chrome holds it back on your site for two hours, and longer after each further close, up to four weeks.

If most of your visitors are signed in to Google and you are happy for Google to hold their identity, One Tap is a sound choice. The alternatives below matter when one of these points is a problem.

What are the alternatives?#

The alternatives keep the one-tap experience and change who holds the accounts: another identity provider, or your own site.

FedCM with another identity provider#

FedCM is a W3C draft standard, and nothing in it is specific to Google. Any identity provider can serve the few JSON endpoints that FedCM needs. Any site with a client ID from that provider can then ask for its prompt with navigator.credentials.get(), and Chrome and Edge show the same kind of prompt as One Tap, with that provider’s accounts.

Seznam, a Czech internet company, uses FedCM to offer Seznam accounts on partner shops. You can also run your own provider if you have several sites that should share one account. How does FedCM work explains the endpoints. The limit is the browser: Safari and Firefox don’t support FedCM as of October 2026, so their users still need a popup or a redirect.

Passkey autofill#

Passkey autofill, also called conditional mediation, puts the passkeys saved for your site into the browser’s autofill list on the username field. One tap and a fingerprint or face scan sign the person in, and no identity provider sits in between. It works in Chrome and Edge 108, Firefox 119 and Safari 16 or later.

The catch is that passkey autofill only helps people who already have an account and a passkey for your site. It doesn’t sign up a new visitor in one tap, and you need WebAuthn code on your server or a passkey service. See How do I add passkeys to my website?

Other one-tap widgets#

Several auth services let you add a one-tap prompt, so check what runs underneath. Clerk’s <GoogleOneTap /> component and Supabase’s One Tap guide both show Google One Tap, with Google accounts. They make One Tap easier to add rather than replace it.

How do the options compare?#

What you build differs too. One Tap needs Google’s script and a server check of Google’s ID token. Your own FedCM provider means building and running the provider side. Passkeys need WebAuthn on your server. A hosted provider needs its script and one server route.

Where loginos fits#

loginos is a hosted OpenID Connect provider, and its browser SDK adds a “Continue as” prompt to your pages. In Chrome and Edge it is the browser’s own FedCM prompt, like One Tap, and the browser can sign returning members in by itself. In other browsers, your button opens a small loginos window that closes itself after sign-in. Your page learns nothing about a visitor until they continue.

Your page gets a one-time code rather than a token, and your server exchanges it with your app secret:

<button id="sign-in">Sign in with loginos</button>

<script src="https://loginos.io/sdk/v1.js"></script>
<script>
  const loginos = Loginos.init({ appKey: "YOUR_APP_KEY" });
  const finish = (result) =>
    result &&
    fetch("/api/auth/login/single/token", {
      method: "POST",
      headers: { "content-type": "application/json" },
      body: JSON.stringify(result), // { code, nonce, via }
    }).then((res) => res.ok && location.reload());

  loginos.prompt().then(finish); // Chrome and Edge: "Continue as …?" on page load
  document.querySelector("#sign-in").onclick = () => loginos.signIn().then(finish);
</script>

The server route exchanges the code at /oauth/token without redirect_uri or code_verifier, and checks that the ID token’s nonce matches. The Continue as docs have the full example, and How do I add a one-tap “Continue as” login? walks through it step by step.

Know the trade-offs before you switch:

• loginos accounts, not Google accounts. loginos has no “Sign in with Google”. People sign in to loginos with a passkey or a password, and one loginos account works on every platform that uses loginos.
• The prompt needs a loginos session. Chrome and Edge show it only to people already signed in to loginos. Everyone else uses your button and creates an account once.
• Sign-in pages live on loginos.io. If you need a login page on your own domain, or SAML for enterprise customers, loginos is not the right fit.

To try it, create an account and a platform in the developer console.

Frequently asked questions#

Does Google One Tap work in Safari and Firefox?#

Not as the normal prompt. Google’s docs say tracking prevention stops the usual One Tap prompt in Safari, Firefox and Chrome on iOS. With itp_support set to true, those browsers show a welcome prompt that opens a popup window, and automatic sign-in isn’t available there.

Is Google One Tap the same thing as FedCM?#

No. FedCM is a browser API that any identity provider can use. Google One Tap is Google’s product, and in Chrome it uses FedCM to show its prompt. In browsers without FedCM, Google’s library uses its own prompt and popups instead.

Can I show Google One Tap and another one-tap prompt on the same page?#

Yes, but don’t start both when the page loads. The FedCM spec lets a browser run only one FedCM sign-in per page at a time, so a second prompt can be rejected. Show one prompt on page load and offer the other provider through its own button.

Do passkeys replace Google One Tap?#

For returning users, they can: passkey autofill gives them a one-tap sign-in with a fingerprint or face scan, and no identity provider is involved. New visitors still need a quick way to create an account, which is what One Tap and other “Continue as” prompts are good at.