Auth0
Hosted authentication with rules you can write yourself
Auth0 handles login for an application and gives you room to change how it behaves. Universal Login hosts the sign-in page, social and enterprise connections cover the identity providers a customer might arrive with, and Actions run your own code at points in the flow - after a login, before a token is issued - which is what teams reach for when the requirement is not standard. It covers both directions: consumer sign-up at volume, and B2B where each customer organisation needs its own SSO connection, directory sync and roles. Attack protection, breached password detection and multi-factor sit on top. It is part of Okta. The free tier is unusually large at 25,000 monthly active users with one enterprise connection; paid plans add features rather than raw volume, and are quoted here at 500 monthly active users since the price scales with that number.
- Universal Login hosts the sign-in page for you
- Social and enterprise identity connections
- Actions run your own code inside the login flow
- Organizations for B2B customers with their own SSO
- Self-service SSO and SCIM directory sync
- Multi-factor authentication and attack protection
- Breached password detection
- 25,000 monthly active users on the free tier
Based on what people have said
Every answer links back to the mentions it came fromHow does Auth0 compare to self-hosted alternatives like Keycloak?
Opinions are divided; some users prefer Auth0 because they find managing Keycloak to be difficult, while others are actively migrating away from Auth0 toward Keycloak to gain more control.
2 mentions · r/sysadmin · Aug 2026
What are the common concerns regarding Auth0 pricing?
Some users find the cost of enterprise features, such as SAML support for B2B customers, to be high, noting that professional plans can start at several hundred dollars per month.
1 mention · @EchoGit42 · Sep 2026
Is Auth0 considered a viable option for B2B and enterprise authentication?
Yes, it is frequently listed alongside other authentication providers for application stacks and is used to handle requirements like SAML and branded login experiences.
3 mentions · r/dotnetMAUI · r/SideProject · r/sysadmin · Aug 2026 – Sep 2026
Are there alternatives that users suggest for those looking to move away from Auth0?
Some users have suggested migrating to platforms like WorkOS when looking for alternatives to Auth0.
1 mention · @initjean · Aug 2026
These summarise counts and dates only. Read the quotes themselves under what people are saying.
What people are saying about Auth0
70% neutral“Interested in what you are using behind the scenes - I am doing a major update on my app, Tripperist, and have and am using OSM / Mapsui, Auth0 for Authentication, Postgresql / GIS for mapping database.”
“Need SAML for the first enterprise customer and B2B Professional starts at $800/mo — that’s Auth0’s own pricing page, checked 2 Sep”
“Options right now: Next.js / TanStack Start / React+Vite, Neon / Supabase / PlanetScale / Turso / MongoDB, Drizzle / Prisma / Mongoose, Better Auth / Clerk / Auth0 / Supabase Auth / Neon Auth, Stripe, Resend / Mailgun / Brevo.”
“why don't they just use Astra to move migrate from Auth0 to something better, e.g. WorkOS???”
“Nothing about that tenant ships in the product; self-hosted installs point at their own IdP (Keycloak, Okta, Entra ID, Auth0, whatever), or just use the built-in local auth, which is the default.”
“3) You can use Auth0 to authenticate *to* other applications, and you can also use other applications to authenticate *into* Auth0.”
“How to achieve Auth0 passwordless sms sign-in with SharePoint painlessly?”
“* Auth0 SSO provider is now supported”
“Also Auth0 exists because Keycloak is a literal pain in the ass. No I don’t work for them but I long ago (5 years) moved customers away from build your own Auth to Auth0, Cognito or Firebase (never Azure’s shit solution).”
“We're on Auth0 today (custom domain for branded login + SAML ACS). We're migrating to Keycloak and need both live at once so we can pilot a few customers first.”