Firebase Authentication review
by Google (Firebase)Authentication and user management
Sign-in for Firebase and Google Cloud apps: 50,000 monthly active users at no cost, then from $0.0055 each, with SAML at $0.015 per user.
- Free plan
- No card needed
- Self-serve
- Usage-based
- Public prices
What you're paying for
- Worth the price (main value)
- Built-in reach
Sign-in that plugs into Firebase and Google Cloud, free to 50,000 monthly users, with SAML at $0.015 per user and a self-serve Google Cloud BAA.
Firebase Authentication gives Firebase and Google Cloud apps email, phone, social and anonymous sign-in with SDKs for iOS, Android, web, C++ and Unity, and its tokens work with the rest of Firebase. With the Identity Platform upgrade, the first 50,000 monthly users and 50 SAML/OIDC users cost nothing on Blaze, and Identity Platform is covered by the Google Cloud BAA customers accept in the console.
- 50,000 monthly users at no costBlaze projects pay nothing up to 50,000 MAU, then $0.0055 per MAU, falling to $0.0025 above 10 million.Evidence: Firebase and Identity Platform pricing pages (2026-10-15)
- SAML priced per userSAML and OIDC users are free up to 50 a month, then $0.015 each, with no per-connection fee.Evidence: Identity Platform pricing (2026-10-15)
- ISO 27001, SOC 2 and a self-serve BAAFirebase Authentication is listed with ISO 27001/27017/27018 and SOC 1/2/3; Identity Platform is covered by the Google Cloud BAA, accepted in the console.Evidence: Firebase privacy and Google Cloud HIPAA pages (2026-10-15)
- Part of the Firebase platformClient SDKs cover iOS, Android, web, C++ and Unity, and signed-in users can be checked by Firebase security rules.Evidence: Firebase Auth docs (2026-10-15)
- Best for
- Mobile and web apps on Firebase or Google Cloud that want email, social and phone sign-in at a low per-user price.
- Good to know
- Authentication runs only in US data centers, and the docs list no passkeys or breached-password checks.
How Firebase Authentication compares
Against 3 other products we reviewed in Authentication and user management: what you pay for with each, the five access facts, the plan limits we recorded and each review's bottom line. The note under the table says how each one was checked.
| Metric | Firebase Authentication | Supabase Auth | Clerk | WorkOS |
|---|---|---|---|---|
| What you're paying for | Worth the priceSign-in that plugs into Firebase and Google Cloud, free to 50,000 monthly users, with SAML at $0.015 per user and a self-serve Google Cloud BAA. | Worth the price100,000 monthly active users on the $25 Pro plan, SSO priced per user, and SOC 2, ISO 27001 and a HIPAA BAA on the self-serve Team plan. | Saves engineering timeReady-made sign-in and user management, free for 50,000 retained users, with SSO and MFA from $25 a month at published prices. | Saves engineering timeEnterprise SSO and directory sync at a published $125 per connection, on top of user management that is free for up to 1 million monthly users. |
| Overall score | 8.4 | 9.3Best | 8.2 | 7.9 |
| Free option | Free plan | Free plan | Free plan | Free plan |
| Card to start | No card needed | –Not measured | No card needed | No card needed |
| Getting access | Self-serve | Self-serve | Self-serve | Self-serve |
| Starter priceCheapest paid plan | $0.0055/MAU above 50,000 | $25/mo | $25/mo | $125/SSO connection/mo |
| Pricing model | Usage-based | Usage-based | Usage-based | Usage-based |
| Pricing page | Public prices | Public prices | Public prices | Public prices |
| Free plan | 50,000 MAU; Spark capped at 3,000 a day | 50,000 MAU; paused after 1 week inactive | 50,000 MRU per app, no card | 1,000,000 MAU, no card until production |
| Entry paid plan at 10,000 users | $0 (Blaze), 50,000 MAU at no cost | $25/mo (Pro), 100,000 MAU included | $25/mo (Pro), $20 billed annually | $0 (users free up to 1M) |
| Enterprise SSO | 50 SAML/OIDC users free on Blaze, then $0.015 each | 50 SSO users on Pro, then $0.015 each | 1 connection on Pro, then $75/mo each | $125/mo per connection (1–15), down to $65 at 51–100 |
| SOC 2 report | SOC 2 (Google), via Compliance Reports Manager | Type 2, on Team ($599/mo) | Type 2, on Business ($300/mo) | Type II, from the Trust Center on request |
| HIPAA BAA | Google Cloud BAA, accepted in the console | Team plan, paid add-on | Enterprise plan | Enterprise plans |
| Data region | US only | 17 AWS regions, EU included | US only | US (per the DPA) |
| Log retention on the entry paid plan | 30 days in Cloud Logging (activity logs, opt-in) | 7 days of auth audit logs (Pro) | 7 days of application logs (Pro) | 90 days of events via the Events API |
| Bottom line | From its public pages, Firebase Authentication is the least expensive route here to SAML SSO and a self-serve BAA, inside the Firebase platform. Check US-only processing and the protections it does not list. | From its public pages, Supabase Auth is the least expensive per user of the three and the only one with a BAA on a self-serve plan. It fits best when the rest of your app runs on Supabase. | From its public pages, Clerk offers the largest free allowance here and clear prices from the first user to SSO. Check US-only hosting and the plan that unlocks the SOC 2 report against your customers’ requirements. | From its public pages, WorkOS offers the largest free user allowance here and clear per-connection prices for enterprise SSO. Budget $125 a month per SSO customer and check US-only hosting. |
Evidence: Firebase Authentication: facts checked 2026-10-15 from its public sign-up and pricing pages, no completed hands-on run; Supabase Auth: facts checked 2026-10-15 from its public sign-up and pricing pages, no completed hands-on run; Clerk: facts checked 2026-10-15 from its public sign-up and pricing pages, no completed hands-on run; WorkOS: facts checked 2026-10-15 from its public sign-up and pricing pages, no completed hands-on run. Prices in USD as listed, excluding tax. "–" means not recorded.
Score
- Pricing clarity
- 10.0 / 10, Excellent
- per-user rate published with no ceiling; extra SSO priced
- Free tier
- 10.0 / 10, Excellent
- 50,000 users
- Price at 10,000 users
- 10.0 / 10, Excellent
- $0/mo (Blaze)
- Enterprise SSO
- 9.0 / 10, Excellent
- SSO on a paid self-serve plan; +$0.75/mo for 5 connections (50 SAML/OIDC users free on Blaze plus 50 at $0.015)
- Compliance documents
- 8.0 / 10, Excellent
- own SOC 2 Type II, ISO 27001, HIPAA BAA self-serve, no region choice
- Security on self-serve plans
- 3.5 / 10, Fair
- MFA: free plan; passkeys: not stated; bot protection: entry paid plan; breached-password checks: not stated; brute-force protection: not stated
Review
Review from public pages
Written from Firebase Authentication's public pages (pricing, security or privacy, and docs) as read on Oct 15, 2026. We did not sign up, and no hands-on run is published yet.
What the public pages show
We read the Firebase and Identity Platform pricing pages, the Firebase Auth overview, limits and privacy pages, and Google Cloud's HIPAA and Identity Platform docs on Oct 15, 2026; we did not sign up for this review. Firebase Authentication comes in two forms. The base product is listed at no cost on both Firebase plans, apart from phone sign-in, which needs the pay-as-you-go Blaze plan. The optional Identity Platform upgrade adds MFA, SAML and OIDC, blocking functions, audit logging, multi-tenancy and an SLA, and switches pricing to monthly active users.
The upgrade's limits deserve a careful read. The pricing page shows 50,000 MAU at no cost, but the docs say upgraded projects on the no-cost Spark plan are limited to 3,000 daily active users, and to 2 a day for SAML and OIDC. The SAML guide also asks you to enable billing first, so in practice enterprise SSO starts on Blaze.
On security, the docs describe SMS and TOTP second factors, reCAPTCHA Enterprise bot protection as a billable add-on, password policies for complexity and email enumeration protection, which is on by default for new projects. We found no documented passkey sign-in and no breached-password check.
Strengths
- SSO at per-user prices
SAML and OIDC users are free up to 50 a month on Blaze, then $0.015 each; five enterprise customers with 100 SSO users add $0.75.
vs WorkOS: WorkOS charges $125 per connection and Clerk $75 per connection after the first.
- Free to 50,000 monthly users
Blaze projects pay nothing up to 50,000 MAU, then from $0.0055 per MAU.
Compared: Auth0’s B2C Essentials is $700 a month at 10,000 users.
- ISO 27001 and a self-serve BAA
Firebase Authentication is listed with ISO 27001/27017/27018 and SOC 2, and Identity Platform is in the Google Cloud BAA you accept in the console.
vs Supabase Auth: Supabase Auth offers its BAA on the $599 Team plan; Clerk and WorkOS on enterprise plans.
- Wide SDK coverage
Sign-in SDKs cover iOS, Android, web, C++ and Unity, with anonymous accounts that can be upgraded later.
Things to know
- US-only processing
The Firebase privacy page says Firebase Authentication runs only from US data centers.
- Spark limits after the upgrade
Upgraded Spark projects are capped at 3,000 daily active users and 2 SAML/OIDC daily active users; the pricing page shows the 50,000 MAU allowance without that cap.
Workaround: Blaze removes the daily cap and still bills nothing up to 50,000 MAU.
- Fewer built-in protections
The docs list no passkey sign-in or breached-password check, and bot protection runs through reCAPTCHA Enterprise, billed after 10,000 assessments a month.
- SMS costs extra
Phone sign-in and SMS MFA need Blaze and are billed per message by country, from $0.01 in the US; the first 10 a day are not billed.
Pricing reality
Without the upgrade, Firebase Authentication is listed at no cost on both plans except phone sign-in, billed per SMS on Blaze. With Identity Platform on Blaze, the first 50,000 monthly active users are free, then $0.0055 per MAU to 100,000, $0.0046 to 1 million, $0.0032 to 10 million and $0.0025 above; SAML/OIDC users are free to 50, then $0.015 each. At 10,000 users that is $0; at 100,000, $275, the figure Google’s own example uses.
Adjacent costs: SMS by destination country, reCAPTCHA Enterprise beyond its free 10,000 assessments ($8 flat to 100,000), Cloud Logging for activity logs kept beyond the default 30 days, and Cloud Run functions for blocking functions.
Exit path
The Firebase CLI’s auth:export command exports user accounts to JSON or CSV, and the console shows the password hash parameters (modified scrypt by default) needed to import them elsewhere.
Compared with
- Pick Firebase Authentication when
- You build on Firebase or Google Cloud and want a BAA you accept in the console rather than on a $599 Team plan.
- Pick Supabase Auth when
- You need an EU hosting region, passkeys, leaked-password protection, or users stored in your own Postgres database.
- Pick Firebase Authentication when
- You need SAML for a few users at $0.015 each rather than $125 per connection, ISO 27001, or a self-serve BAA.
- Pick WorkOS when
- You want passkeys, breached-password rejection and bot detection built in, and 1 million free users.
- Pick Firebase Authentication when
- You want ISO 27001, a self-serve BAA and SSO priced per user rather than $75 per extra connection.
- Pick Clerk when
- You want prebuilt sign-in UI with bot protection and breached-password checks on the free plan.
Choose it if
- Your app already runs on Firebase or Google Cloud.
- You need a few SAML users per customer at per-user prices.
- You want ISO 27001 and a BAA without an enterprise contract.
Look elsewhere if
- User data must be processed outside the US.
- You need passkeys or breached-password checks today.
Bottom line
From its public pages, Firebase Authentication is the least expensive route here to SAML SSO and a self-serve BAA, inside the Firebase platform. Check US-only processing and the protections it does not list.
Plan limits at a glance
| Limit | As recorded |
|---|---|
| Free plan | 50,000 MAU; Spark capped at 3,000 a day |
| Entry paid plan at 10,000 users | $0 (Blaze), 50,000 MAU at no cost |
| Enterprise SSO | 50 SAML/OIDC users free on Blaze, then $0.015 each |
| SOC 2 report | SOC 2 (Google), via Compliance Reports Manager |
| HIPAA BAA | Google Cloud BAA, accepted in the console |
| Data region | US only |
| Log retention on the entry paid plan | 30 days in Cloud Logging (activity logs, opt-in) |
Read from the vendor's public pages on Oct 15, 2026. No hands-on run is published yet. How we check
We have not published a sign-up run for Firebase Authentication yet. The access facts above were read from its sign-up and pricing pages on Oct 15, 2026.
We have not published API calls for Firebase Authentication yet.
Firebase Authentication lists 2 plans. The cheapest paid plan, Blaze (pay as you go), costs $0.0055/MAU above 50,000.
- Firebase AuthenticationFreeSpark$0/moWith Identity Platform: 3,000 daily active users, 2 a day for SAML/OIDC
- No payment method needed
- Email, social, anonymous and custom sign-in
- TOTP MFA after the Identity Platform upgrade
- No phone sign-in
- Firebase AuthenticationBlaze$0.0055/MAUAfter 50,000 free MAU; $0.0046 from 100,000, $0.0032 from 1M, $0.0025 from 10M
- SAML/OIDC: 50 MAU free, then $0.015 each
- Phone sign-in and SMS MFA billed per SMS ($0.01 in the US)
- First 10 SMS a day not billed
- Identity Platform SLA
Prices as listed, USD, excluding tax; observed 2026-10-15.
Source: firebase.google.com pricing page. Prices change; the observed date above is when our agent read them.