Stack
Clerk
A hosted authentication service that provides prebuilt React and Next.js sign-in components and manages users, sessions, and social login for you.
What it actually does
Clerk handles the login layer of an app so you do not build sign-in screens, password resets, or session handling yourself. You drop in components like SignIn, UserButton, and OrganizationSwitcher and get working auth on a React or Next.js stack.
The free tier covers 50,000 monthly retained users with social login, magic links, and multi-factor auth. New users are free for their first 24 hours and there is a one-month grace period when you cross a limit, so signup spam does not immediately inflate the bill.
The catch is add-ons. Business-to-business features (customer-facing organizations) cost an extra $100/mo on top of the $25 Pro plan, and per-user overage past 50k is $0.02 each, so 100k users runs roughly $1,025/mo.
Clerk vs its main rivals
The tools people actually weigh against Clerk: Auth0, Supabase Auth, WorkOS AuthKit, Stytch. Same criteria for every column, including where Clerk loses.
| Clerk |  Auth0 |  Supabase Auth |  WorkOS AuthKit | SStytch | |
|---|---|---|---|---|---|
Pricing & access | |||||
| Free tier | Unknown50k MRU | Unknown25k MAU | Unknown50k MAU | Unknown1M MAU | Unknown10k MAU |
| Starting price | $25/mo | $35/mo | $25/mo | $0 + add-ons | $0 / usage |
| Custom domain | YesPro | YesFree tier | YesPro | Yes$99/mo | YesYes |
Login methods | |||||
| Prebuilt hosted UI | YesYes | YesUniversal Login | NoNo | YesAuthKit | YesComponents |
| Social login | YesFree | YesFree | YesFree | YesFree | YesFree |
| MFA / passkeys | YesFree | YesYes | YesBasic | YesFree | YesYes |
B2B & enterprise | |||||
| Organizations / B2B | Yes+$100/mo | YesPaid | NoNo | YesFree | YesB2B plan |
| Enterprise SSO (SAML) | YesAdd-on | Yes1 free | YesPro | Yes$125/conn | YesYes |
| Directory sync (SCIM) | YesAdd-on | YesPaid | NoNo | Yes$125/conn | YesYes |
Developer & data | |||||
| REST API & SDKs | Free | Free | Free | Free | Free |
| Webhooks | Free | Free | Free | Free | Free |
| Self-host / data ownership | NoNo | NoNo | YesYes | NoNo | NoNo |
- Drop-in React and Next.js sign-in components replace building custom auth UI
- 50,000 free monthly retained users, with new users free for their first 24 hours
- One-month grace period when you cross a limit softens sudden overage
- Customer-facing B2B organizations cost an extra $100/mo, so real B2B starts near $125/mo
- No hosted user store you can self-host; users live in Clerk, so leaving means a migration
- Per-user overage of $0.02 makes 100k users about $1,025/mo, far above the $25 base
Pay less for it
5 ways foundPro drops to $20/mo billed annually, saving about 20% versus $25/mo monthly.
50,000 monthly retained users at $0 covers most solo projects before any charge.
Clerk offers free Pro credits to eligible early-stage and accelerator-backed startups.
The $100/mo organizations add-on is optional; pure B2C apps stay on the $25 base.
Better Auth — Open-source, self-hosted, zero per-user cost with the same social login and MFA if you are comfortable owning the auth code.
StackTracker tracks what you actually pay for Clerk and every other tool, flags overpayment, and shows the dollars you would save by switching.
Is it the right tool for you
- You are on Next.js or React and want prebuilt sign-in UI without building it
- You are B2C and unlikely to pass 50,000 users soon
- You value prebuilt user-management screens over data ownership
- You need customer-facing organizations without a $100/mo surcharge → use Kinde
- You want zero per-user cost and to keep users in your own database → use Supabase Auth or Better Auth
Track what Clerk 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.