Udibo vs Firebase Authentication

Firebase Authentication gives you client SDKs for web and mobile, email and social sign-in at no published cost, and a token that Firebase's own databases trust. Udibo gives you hosted sign-in behind a standard OAuth 2.0 boundary, with organizations, roles, and resource permissions included on every plan. The difference that decides most evaluations: Firebase is free until you need multi-factor authentication or audit logs, which move a project to Identity Platform and per-user pricing, and it leaves organizations and per-resource permissions to your code. Udibo includes those on Free and charges as you grow.

Checked September 8, 2026 against Firebase's pricing page and Identity Platform pricing. Udibo's prices are on its pricing page.

Additional details reviewed October 2, 2026: Udibo usage assumptions and API access, plus Firebase's federated-user limits, email quotas, and custom email delivery. Other vendor claims use the check date above.

The short version

Why teams pick Udibo over Firebase Authentication

• Organizations are a product, not a pattern. Firebase has no organization object; a customer's company and its members are yours to model, and roles ride in custom claims capped at 1,000 bytes. Udibo ships organizations with invitations, memberships, and roles on every plan, with no cap on organizations or members, and a person can hold a different role in each.

• Permissions checked from the backend you run. Register the permissions your application interprets, attach them to roles across a tenant, inside an organization, or on one resource, and read the result from the token or a hosted check over HTTPS. Firebase Security Rules decide access inside Firestore, Realtime Database, and Cloud Storage; a backend elsewhere gets an ID token and custom claims, and per-resource checks are yours to build.

• MFA and audit history on Free. Firebase's multi-factor authentication and its audit logging come with the Identity Platform upgrade, which changes the pricing model. On Spark, the daily limits are 3,000 active users for Tier 1 providers such as email and social sign-in, and 2 for Tier 2 providers (SAML and OpenID Connect). Udibo's Free plan includes authenticator-app MFA with recovery codes and at least 90 days of audit history exportable as CSV or NDJSON.

• Federated users cost the same as everyone else. Identity Platform bills SAML and OpenID Connect users at $0.015 per monthly active user after the first 50 per project, about $15 per 1,000. Udibo connects any OpenID Connect provider with no per-connection fee, and a federated user is a retained user at the same $3 per 1,000 as any other. SAML is not available on Udibo today.

• A standards boundary instead of a client library per platform. Your application talks to Udibo through OAuth 2.0 and OpenID Connect, with the active organization and its roles in the token. Use an OpenID Connect client that supports your application's flow. A shared protocol reduces sign-in coupling; changing provider still needs identity mapping, session changes, and a review of claims and permissions.

• Your brand on the pages you did not build. Udibo hosts the sign-in, recovery, and MFA pages with your name, logo, and colors and no vendor badge on any plan. Firebase leaves the sign-in page to you. Its Google-sent templates let you change the sender, reply-to, and subject, but the message body only for password resets. For fully custom verification and sign-in messages, use Admin SDK action links with your own email service; you build and send those messages.

• Lower user-only costs in the larger scenarios below. Identity Platform charges $0.0055 per monthly active user from 50,000 to 100,000 and $0.0046 from there to 1,000,000; Udibo's rate is $3 per 1,000 retained users. At 1,000,000 users that is $4,415 against about $2,990, before other usage. Identity Platform's email and social sign-in user allowance is 50,000; Udibo is also free within 500 retained users and its other Free allowances.

Why Firebase Authentication may still be the right choice

• Free sign-in with no published user limit. Email, social, anonymous, and custom sign-in are included on both the Spark and Blaze plans, and the pricing page lists no monthly active user charge for them unless a project upgrades to Identity Platform. An app that needs neither MFA nor audit logs pays nothing for authentication at any published scale.

• Client SDKs and the Firebase data model. Firebase's SDKs for web, Apple, Android, C++, and Unity sign people in from inside the app, and Firestore, Realtime Database, and Cloud Storage trust the result through Security Rules. Udibo has no mobile SDK, and its tokens do not drive Security Rules.

• Phone and anonymous sign-in. Firebase offers phone sign-in on the Blaze plan, billed per SMS, and anonymous accounts that can be upgraded later. Udibo offers neither today.

• SAML, blocking functions, and tenants. Identity Platform adds SAML (web only), functions that run before registration and sign-in complete, and tenants that silo users and configuration within one project. Udibo does not offer SAML, SCIM, or hosted passkeys.

Pricing side by side

Firebase and Identity Platform prices follow the September 8, 2026 check, with the October 2 limit and email review noted above. Udibo's pricing assumptions were reviewed October 2. The two count people differently: Identity Platform bills a monthly active user, "any account that has signed in within a given month", and Udibo prices a retained user: "A person who returns more than 24 hours after creating their account counts once in that UTC calendar month." The examples below assume every person counted is active that month on both sides.

Three worked examples, with the same assumptions on both sides:

The 5,000-email scenario assumes Blaze: Google's Spark plan sends at most 5 email-link sign-in messages a day. The $0 figures do not include an external email service for fully custom messages.

Sources: Firebase pricing, Identity Platform pricing, the Firebase Authentication overview for what the upgrade adds and its Spark limit, and Udibo's pricing page. All change; check the vendor's current page before you decide.

Cost at scale

Users only, on the plan that gives you MFA, assuming every person counted is active that month on both sides. Udibo's figures are its published rates; Firebase's are Identity Platform's published tiers on the Blaze plan, priced band by band the way Google's own pricing examples do.

Without the Identity Platform upgrade, Firebase publishes no per-user charge for email and social sign-in at any scale. Udibo also has no charge within 500 retained users and its other Free allowances, then prices usage on Standard.

For email and social sign-in on Identity Platform, the first 50,000 monthly active users have no user charge. Comparing the same user counts on both sides, the user-only bills are close at 100,000, and Udibo Standard becomes lower at roughly 110,000 through the 1,000,000-user scenario shown above. These are user-only comparisons, not total bills or a claim about every higher tier. Federated users have a separate rate: 10,000 OpenID Connect users cost about $149 a month on Identity Platform and $20 on Udibo, when tenant-wide sign-in options fit your application. Email, hosted checks, and other services can change the complete cost.

What the integration looks like

With Udibo, register an application and its callback, send people to the hosted sign-in page, and finish the authorization-code flow on your server. Your backend holds the session and the browser gets a cookie, never a token. The first-login guide walks each checkpoint, and the organizations and permissions guides cover a person with a different role in each of two organizations.

With Firebase, the client SDK signs people in from inside your app and hands back an ID token that Firestore, Realtime Database, and Cloud Storage trust through Security Rules; a backend elsewhere verifies it with the Admin SDK (verify ID tokens). FirebaseUI is Firebase's drop-in UI for the common sign-in methods (FirebaseUI).

A Firebase client often uses identity in more places than the login screen. Before comparing providers, list the database, storage, and server endpoints that trust the current user. Udibo's hosted flow gives your application identity through OAuth 2.0 and OpenID Connect, and your backend applies the organization and resource checks; nothing translates those checks into Security Rules. A valid session says who someone is; your backend still decides what they may read.

Where Udibo needs a closer look

Udibo does not currently offer hosted passkeys, SAML, SCIM, phone sign-in, or anonymous accounts, and there is no mobile SDK or UI kit. The @udibo/oauth2 package supplies protocol building blocks, not drop-in components. Customers administer tenants through the dashboard today; there is no self-serve management API credential for a script or backend. See the API guide. If anonymous-to-registered upgrades, phone sign-in, mobile recovery, or a Security Rule that depends on the signed-in user is essential, demonstrate the complete target workflow before committing; a successful login alone does not establish parity.

Moving an existing Firebase application

Inventory anonymous users, linked providers, custom claims, Security Rules, and code that assumes a Firebase UID. Keep your application's stable user ID and record the mapping from the old issuer and subject to the new one; do not use email alone as an automatic account-linking rule. Test every Security Rule and backend verifier affected by a new token, and do not weaken a rule to make a different issuer's token appear valid. Firebase's scrypt variant (Firebase scrypt) is not the standard scrypt encoding the import contract accepts, so check it against a real export and plan a reset path. Existing sessions and MFA enrollment do not move with a profile. See migration planning.

Try next: complete one Udibo login, then give a person two organizations and a different role in each. Before you have an account, the agent integration brief lets your coding assistant prepare the integration.

Frequently asked questions

Is Udibo cheaper than Firebase Authentication? On user charges alone, both can cost $0 for a small app within Udibo's 500 retained users and other Free allowances. Firebase's base email and social sign-in have no published user charge; Identity Platform includes the first 50,000 email/social monthly active users. From 501 through 50,000 retained users, Udibo Standard's user-only price is $5 to about $140, assuming other usage fits its allowances. Udibo includes organizations, roles, resource permissions, MFA, and audit history that you would otherwise assemble around Firebase. For Identity Platform's email and social sign-in, the equal-user-count examples above favor Udibo from roughly 110,000 through 1,000,000 users; OpenID Connect federation uses a separate rate. Add email, hosted permission checks, SMS, and other services before comparing the complete bill.

Does Udibo have client SDKs and phone sign-in like Firebase? No. Udibo hosts the sign-in, recovery, and MFA pages and returns to your app through OAuth 2.0; there is no mobile SDK, no UI kit, and no phone or anonymous sign-in. Choose an OpenID Connect client library that supports your application type and callback flow, and test that complete journey. The account screens inside your product are yours to build.

Can I move from Firebase to Udibo without making users re-register? Profiles and social identities can be imported and linked by the provider's stable subject. Firebase's scrypt password hashes are not in a format Udibo's import accepts, so plan a password reset on first sign-in; MFA enrollments, anonymous accounts, and active sessions do not move. See migration planning and user import.

Do I need Identity Platform for MFA on Firebase? Yes. Firebase documents SMS and TOTP multi-factor authentication for projects upgraded to Firebase Authentication with Identity Platform. Email/social MAU charges start past 50,000 on Blaze; SAML and OpenID Connect have a separate allowance and rate. Spark's daily limits are 3,000 Tier 1 active users and 2 SAML/OpenID Connect active users. Udibo includes authenticator-app MFA with recovery codes on Free and does not offer SMS factors.

Last verified 2026-10-02.