Clerk
3 known investors
Clerk provides authentication and user management for developers, offering drop-in UI components and SDKs for sign-in, profile and organization management, multi-tenancy, and subscription billing. It targets B2C and B2B SaaS applications built on modern web and mobile frameworks.
Also known as Clerk.com Β· Clerk.dev
Founders & leadership
Investors Β· 3
Also in the syndicate Β· 2
Company profile
researched Aug 2026Clerk is a developer platform for authentication and user management. It ships drop-in UI components β such as <SignUp/>, <SignIn/>, <UserButton/>, <UserProfile/> and <Waitlist/> β alongside APIs and admin dashboards that let teams add sign-up, sign-in, profile management and account security to an application without building the underlying flows. Components can be styled with any CSS library and deployed on the customer's own domain.
Beyond sign-in, Clerk offers organization/multi-tenancy features aimed at B2B SaaS: organization creation and switching, membership and invitation management, custom roles and permissions, auto-join based on verified email domains, and organization profile and billing UIs. A Billing product lets developers define and manage subscription plans, unify user and subscription data, gate access to content and display pricing tables for B2C and B2B applications without writing payment code or handling webhooks. Additional capabilities include multifactor authentication, session lifecycle management with device monitoring and session revocation, social sign-on with 20+ providers, email and SMS one-time passcodes, magic links, password authentication with breach detection, bot detection, fraud and abuse prevention (blocking disposable email domains and email subaddressing), and issuance of end-user API keys.
The platform is distributed through SDKs for frontend frameworks including Next.js, React, Expo, TanStack React Start, React Router, Astro, Nuxt, Vue, JavaScript, Chrome extensions, iOS and Android, and backend SDKs for Express, Fastify, Go, Java, PHP, Python, C# and Ruby on Rails, with community-maintained integrations for Angular, Elysia, Flutter, Hono, Koa, Rust, SolidJS, Svelte and Tauri. Clerk also provides a CLI and agent-oriented setup instructions (clerk.com/SKILL.md) intended for AI coding tools, plus database integrations that let Clerk-managed users authenticate directly against a customer database.
Founding story
Clerk was founded in March 2019 by Braden Sidoti and Colin Sidoti, with a stated mission to solve user management for developers. Andrew Miklas, co-founder of PagerDuty, joined the board when the company raised its seed round in 2021.
Business model
Clerk sells a hosted user-management and authentication platform to software developers on a self-serve, usage-based subscription. A free tier covers a customer's first 50,000 monthly retained users and 100 monthly retained organizations with no credit card required, with paid usage beyond that.
Subscription pricing tied to monthly retained users and organizations, with a free allowance of 50,000 monthly retained users and 100 monthly retained organizations before paid tiers begin. Its Billing product also lets customers run their own subscriptions on Clerk.
Traction
At its Series B in March 2023, Clerk reported managing more than 16 million end-users and facilitating over one new sign-up per second. The company had previously announced surpassing one million managed users. Its DEV Community organization account has published 53 posts since joining in April 2021.
Latest developments
In October 2025 Clerk announced a $50 million Series C, promoted on its homepage; reporting states the capital is intended to accelerate the product roadmap, expand engineering, sales and customer success teams, and scale infrastructure. Recent product work includes Clerk Billing for B2C and B2B subscriptions, API keys for end users, a waitlist component, fraud and abuse prevention controls, and a CLI plus agent-oriented setup instructions for AI coding tools.
βΈFull profile β market position, technology, go-to-market, geography, history
Market position
Clerk positions itself in the developer tools and identity management market as a complete user management platform rather than a sign-in box, extending from authentication into authorization and subscription billing. It is backed by Andreessen Horowitz, CRV, Madrona and Stripe, and counts angel investors from Vercel, PagerDuty, Segment, Auth0 and other developer-tooling companies.
Clerk emphasizes prebuilt, brand-customizable UI components ("components are the new APIs") that cover authentication, profile, organization management and billing, rather than APIs alone, and bundles multi-tenancy and Stripe-integrated subscription billing so developers avoid writing payment code or handling webhooks.
Technology
Clerk combines prebuilt React and multi-framework UI components with backend APIs, SDKs, a CLI and a hosted dashboard. Security features include multifactor authentication, session management with active device monitoring and revocation, machine-learning bot detection, brute-force prevention on one-time passcodes, password breach detection, and support for social sign-on, magic links and API key issuance. The company states it is SOC 2 Type 2 and CCPA compliant and conducts regular third-party audits and penetration tests.
Go-to-market
Distribution is developer-led: free-tier self-serve signup, extensive quickstarts and SDK reference documentation, framework-specific guides, a public Discord community, and technical content published on channels such as DEV Community. Clerk also publishes agent-readable setup instructions and a CLI so AI coding agents can install and configure it.
Developers and engineering teams building B2C and B2B SaaS applications on modern web and mobile frameworks, including multi-tenant SaaS products and companies in SaaS, fintech and e-commerce verticals.
Geography
Clerk describes itself as a globally distributed team.
History
Clerk was founded in March 2019 by Braden Sidoti and Colin Sidoti and has been building its authentication foundations since 2019. It raised a $4 million seed round led by S28 Capital announced in July 2021, a $15 million Series A led by Madrona in 2022, and a $30 million Series B led by CRV with participation from Stripe, Andreessen Horowitz and Madrona in March 2023; CRV lists June 2023 as the date it partnered with the company. In October 2025 Clerk announced a $50 million Series C. Over time the product expanded from authentication into organizations/multi-tenancy, authorization and subscription billing.
Compiled by commissioned research from 8 cited public sources β announcements, filings, and press listed under research sources below.
Key figures
latest reportedCompany-reported or press-reported figures, each dated to when it was claimed β not independently audited.
Timeline Β· 7
launches, deals, and filingsClerk announced a $50 million Series C, promoted on its homepage; the capital is reported to be directed at accelerating the product roadmap, expanding engineering, sales and customer success teams, and scaling infrastructure.
$50M source β
Clerk published guidance on adding subscriptions to SaaS applications with Clerk Billing.
Series B led by CRV (Reid Christian, General Partner), with participation from Stripe and existing investors Andreessen Horowitz and Madrona, to expand from authentication into authorization.
$30M source β
Clerk reported managing more than 16 million end-users and facilitating over one new sign-up per second across SaaS, fintech and e-commerce verticals.
Clerk announced a partnership with Stripe to tightly integrate Stripe Billing, enabling developers to subscribe users to plans and grant feature access based on the purchased plan without webhooks.
$15M source β
Seed round led by S28 Capital, with Andrew Miklas (co-founder of PagerDuty) joining the board, to build a next-generation authentication and user management platform for developers.
$4M source β
Dated company events from announcements, filings, and press; legal rows summarize public dockets and regulator releases.
βΈResearch sources Β· 8
primary sources listed
- Clerkclerk.dev Β· web
8 public sources were cited for this profile; the first-party ones are listed here.
Frequently asked questions
- What does Clerk do?
- Clerk provides full-stack authentication, user management, multi-tenancy and subscription billing for developers.
- Who founded Clerk?
- Clerk was founded by Braden Sidoti.
- Who are Clerk's investors?
- Clerk's investors include Mango Capital.