Stack
Auth0
An Okta-owned hosted identity platform covering login protocols, social and enterprise connections, and MFA across web, mobile, and API stacks.
What it actually does
Auth0 is a hosted identity service, now part of Okta. It supports a wide range of login protocols and identity providers, which matters when an enterprise customer audits your security during a sales cycle.
The free tier is large on paper: 25,000 monthly active users, a custom domain, unlimited social connections, and one enterprise SSO connection with no credit card. Founders often choose Auth0 for the brand name on a security questionnaire rather than the price.
The problem is the cliff. Paid tiers price from the first user, not from 25k, so 10,000 MAUs on B2C Essentials reaches about $700/mo and overage is $0.07 per user. Plan a migration before you outgrow free.
Auth0 vs its main rivals
The tools people actually weigh against Auth0: AWS Cognito, Clerk, WorkOS AuthKit, Firebase Auth. Same criteria for every column, including where Auth0 loses.
| Auth0 |  AWS Cognito |  Clerk |  WorkOS AuthKit |  Firebase Auth | |
|---|---|---|---|---|---|
Pricing & access | |||||
| Free tier | Unknown25k MAU | Unknown10k MAU | Unknown50k MRU | Unknown1M MAU | Unknown50k MAU |
| Starting price | $35/mo | Usage | $25/mo | $0 + add-ons | Usage |
| Overage per MAU | $0.07 | $0.015 | $0.02 | Free to 1M | $0.0055 |
| Custom domain | YesFree | YesYes | YesPro | Yes$99/mo | YesYes |
Login methods | |||||
| Protocol coverage | YesExtensive | YesBroad | YesCommon | YesBroad | YesCommon |
| Social login | YesFree | YesFree | YesFree | YesFree | YesFree |
| MFA / passwordless | YesYes | YesYes | YesFree | YesFree | YesSMS billed |
| Prebuilt hosted UI | YesUniversal Login | YesHosted UI | YesYes | YesAuthKit | NoNo |
B2B & enterprise | |||||
| Organizations | Yes5 free | YesUser pools | Yes+$100/mo | YesFree | NoNo |
| Enterprise SSO (SAML) | Yes1 free | YesYes | YesAdd-on | Yes$125/conn | Yes50 MAU |
| Audit logs | YesYes | YesCloudTrail | YesLimited | Yes$125/SIEM | YesCloud Logging |
Developer & data | |||||
| REST API & SDKs | Free | Free | Free | Free | Free |
| Self-host | NoNo | NoNo | NoNo | NoNo | NoNo |
- 25,000 free MAUs with a custom domain and one enterprise connection included
- Broad protocol and identity-provider coverage that reassures enterprise auditors
- Recognized brand under Okta that answers the 'what auth do you use' question on questionnaires
- Paid pricing prices from user one, so 10k MAUs on Essentials reaches roughly $700/mo
- Overage of $0.07 per MAU is the most expensive in this category
- Extra enterprise SSO connections cost $100/mo each and M2M token add-ons pile on
Pay less for it
5 ways found25,000 MAUs at $0, including a custom domain and one enterprise connection.
Yearly is 11x monthly, so paying annually gives roughly one month free.
Eligible early-stage startups get discounted or free access up to higher MAU caps for a year.
Move to a per-MAU-cheaper provider before crossing 25k to avoid the jump to hundreds per month.
Clerk — Similar hosted UI and social login at $25/mo with $0.02 overage instead of Auth0's $0.07, unless you specifically need the Auth0 brand.
StackTracker tracks what you actually pay for Auth0 and every other tool, flags overpayment, and shows the dollars you would save by switching.
Is it the right tool for you
- Enterprise buyers require a recognized identity vendor on security reviews
- You need wide protocol and identity-provider coverage out of the box
- You will realistically stay under 25,000 MAUs for a while
- You are a price-sensitive B2C app that will cross 25k users → use Supabase Auth or Firebase Auth
- You only need enterprise SSO you can bill back to customers → use WorkOS
Track what Auth0 and the rest of your stack cost
StackTracker adds up every subscription, plus your hours, so you see the real number.
Prices and limits last verified 2026-07-20.