If you’re wondering how to get started with Clerk for beginners, the honest answer is that Clerk’s free tier is one of the most generous in auth: 50,000 Monthly Retained Users per app with no credit card required. The catch is understanding that Clerk bills on MRU, not MAU — which actually works in your favor for most indie projects.
StacksFree Verdict: 8/10 — Clerk’s generous 50K MRU free tier lets indie hackers ship auth without upfront costs, but understanding MRU vs. MAU billing is crucial to avoid surprises.
How This Guide Was Built
This guide is based on official documentation, pricing pages, and community reports — we did not run the tool hands-on. We verified Clerk’s free tier limits, signup flow, and first-project steps against Clerk’s official pricing page and Clerk’s official documentation. We did not test the paid tier — steps are based on official docs. Last verified: August 2026.
What Is Clerk, and What Does It Replace?
Clerk is a complete user management platform providing pre-built, customizable sign-up and sign-in UI, session management, and user profile features. It replaces the need to build authentication flows, session handling, and user database schemas from scratch. Instead of wiring Passport.js or NextAuth.js, or integrating raw JWT logic, you get drop-in React components, a backend SDK, and a management dashboard.
How Do I Get Started with Clerk?
You get started with Clerk by signing up for a free account, creating an application in the dashboard, and installing the SDK for your framework. The fastest path is a Next.js App Router project: install @clerk/nextjs, add your API keys, wrap your app in <ClerkProvider>, and add the prebuilt sign-in components. The Clerk’s official documentation walks through each step.
Here’s the full quickstart sequence, straight from Clerk’s Next.js quickstart:
- Create a project with
npm create next-app, then install Clerk withnpm install @clerk/nextjs. - Add
NEXT_PUBLIC_CLERK_PUBLISHABLE_KEYandCLERK_SECRET_KEYto your.envfile — new apps can skip this because Clerk auto-generates temporary keys. - Create a
proxy.ts(ormiddleware.tson Next.js ≤15) exportingclerkMiddleware()so your routes are protected. - Wrap your root layout in
<ClerkProvider>and add<SignInButton>,<SignUpButton>, and<UserButton>components. - Run
npm run dev, open localhost:3000, and create your first user. - Alternatively, use the Clerk CLI:
npm install -g clerk, thenclerk auth loginandclerk init --framework nextto scaffold automatically.
What’s Included in the Clerk Free Tier in 2026?
Clerk’s free Hobby plan includes 50,000 Monthly Retained Users (MRU) per app with unlimited applications and no credit card required Clerk’s official pricing page. An MRU only counts when a user returns at least 24 hours after signing up — Clerk calls this “First Day Free” — so one-time signups never cost you anything Clerk’s official pricing page.
Clerk Free Tier Limits (Hobby Plan)
| Feature | Limit |
|---|---|
| Monthly Retained Users (MRU) | 50,000 per app |
| Applications | Unlimited |
| Primary Auth Methods | Email/Password, Email Codes, Magic Links, Usernames, Sign-In Tokens, Web3 Wallets |
| Social OAuth Connections | Up to 3 per app |
| Organizations | 100 per app, 20 members per org |
| Dashboard Seats | 3 |
| User Impersonations | 5 |
| API Key Creations | 1,000 / month |
| API Key Verifications | 100,000 / month |
| Session Lifetime | 7 days (fixed) |
What’s Not Included on the Free Tier?
Clerk’s free tier excludes passkeys in production, multi-factor authentication (MFA), SMS-based login, and enterprise SSO (SAML/OIDC) — these all require a paid plan Clerk’s official pricing page. You’re also capped at three social OAuth connections on the Hobby plan, and application logs are retained for only one day Clerk’s official pricing page. Custom email templates, custom password requirements, allowlists/blocklists, user bans, simultaneous sessions, and satellite domains are also paid-only on Hobby Clerk’s official pricing page.
There is no published monthly email-send cap on the free tier Clerk’s official pricing page. If you exceed 50,000 MRU, Clerk gives you a one-month grace period during which your app keeps running normally, after which an upgrade to Pro is required; Pro costs $25/month monthly or $20/month billed annually, with overage at $0.02 per MRU above 50K Clerk’s official pricing page. Business is $300/month monthly or $250/month billed annually, and Enterprise is custom (annual only) Clerk’s official pricing page.
Machine Authentication on the Free Tier
Machine-to-machine auth is included on Hobby with hard monthly caps: 1,000 API key creations and 100,000 API key verifications per month, plus 2,500 M2M token creations and 100,000 M2M token verifications per month Clerk’s official pricing page. Unlike the MRU limit, which has a grace period, these are hard per-month caps — once you hit them, further creations/verifications are blocked until the next month Clerk’s official pricing page.
B2B Authentication (Organizations) on the Free Tier
Organizations are free on every plan: 100 Monthly Retained Organizations (MRO) per app, up to 20 members per organization, with Admin and Member roles, custom permissions, and invitations Clerk’s official pricing page. If you exceed 100 MRO, you must upgrade to the B2B Authentication add-on at $100/month ($85/month billed annually) Clerk’s official pricing page.
Platform Rate Limits
Clerk applies rate limits at the platform level regardless of plan Clerk’s system limits guide. The Frontend API allows 5 Create SignIn and 5 Create SignUp requests per 10 seconds per user/IP, with Attempt SignIn capped at 3 per 10 seconds. The Backend API allows 1,000 requests per 10 seconds in production and 100 per 10 seconds in development, per instance and Secret Key. Invitations are capped at 100 per hour (25 bulk), and org invitations at 250 per hour (50 bulk) Clerk’s system limits guide.
Development vs. Production Instances
Clerk has no traditional free trial — every app gets development and production instances, and all Pro features are usable in development instances Clerk’s official pricing page. That means you can evaluate paid features like MFA or custom email templates in development without paying; the paid plan only matters for production traffic.
Framework Support (Official vs. Community)
Clerk officially supports Next.js, React, vanilla JavaScript, Vue, Nuxt, Astro, Remix, React Router, Expo, Chrome Extensions, and native Android/iOS on the frontend, with Express, Fastify, Go, Ruby, C#, Java, PHP, and Python on the backend Clerk’s official documentation. Community-maintained adapters exist for Svelte/SvelteKit, Angular, Flutter, SolidJS, Hono, Koa, Elysia, Rust, and Tauri — there is no official Svelte SDK, so if you’re on Svelte, budget for the community adapter Clerk’s official documentation.
How Does Clerk Compare to Other Free-Tier Auth Options?
Clerk bills by Monthly Retained Users rather than Monthly Active Users, which makes its free tier cheaper in practice than MAU-based competitors for apps where many signups never return. It also ships a more polished pre-built UI and auth methods like magic links out of the box, which beginners don’t have to assemble themselves.
Compared to Supabase Auth, Clerk is a standalone auth provider rather than part of a backend bundle — Supabase’s 50,000 MAU auth allowance is included with its database platform, which is the right call when you want the whole stack (Supabase free tier guide). Firebase Auth integrates deeply with Google services and is a strong choice for Firebase users. Auth0 is the other major hosted-auth option, though its free tier is aimed at lighter user volumes than Clerk’s 50K MRU.
Common Mistakes Beginners Make
Most beginners confuse MRU with a raw user count, forget that only returning users are billed, or try to use paid features like passkeys and MFA on the free tier. Planning for the three-social-connection cap and the 50K MRU grace period avoids most surprises.
Another common error is over-relying on social logins without planning for users who lack accounts on those platforms, potentially locking out part of your audience. Finally, not understanding the fixed 7-day session lifetime can lead to surprise re-logins in production.
FAQ
What happens when I exceed 50,000 MRU on Clerk’s free tier?
When you exceed the 50,000 MRU limit on the Hobby plan, Clerk provides a one-month grace period to allow you to evaluate the situation. After this period, you are required to upgrade to a paid plan like Pro to continue service. The Pro plan has a $25/month base fee and charges $0.02 per MRU above the 50K included threshold.
Does Clerk work with frameworks other than Next.js?
Yes, Clerk provides official SDKs for a wide range of technologies. While the quickstart is often shown with Next.js, you have official support for React, Vue, Nuxt, Astro, Remix, React Router, Expo for React Native, and native Android and iOS apps. Backend SDKs are available for Express, Fastify, Go, Ruby on Rails, and more. Svelte, Angular, and Flutter integrations are maintained by the community.
Is Clerk free for commercial applications?
Yes, Clerk’s Hobby plan can be used for commercial applications. There are no restrictions on using it for commercial products, provided you stay within the free tier limits and comply with Clerk’s terms of service. This makes it an excellent choice for indie hackers launching SaaS products.
Where to Go Next
Ready to build your stack? Add Clerk to your stack on StacksFree for quick access. To understand other parts of your free-tier architecture, explore our guides on essential services. Learn about hosting with our Vercel free tier guide, transactional email via Resend’s free tier, a serverless Postgres database with our Neon free tier guide, and product analytics using PostHog’s free tier.