Clerk vs Seamless Auth
Clerk
clerk.com
Seamless Auth
seamlessauth.comSide by side
| Figure | Clerk | Seamless Auth |
|---|---|---|
| Price from | $1.67/mo | $49/mo |
| Free plan | Yes | — |
| Free trial | — | Yes |
| Open source | — | — |
| Web | Yes | Yes |
| iOS | Yes | Yes |
| Android | Yes | Yes |
| API | Yes | Yes |
| Self-hosted | — | Yes |
| Plans published | 4 | 4 |
| Spec score · Passwordless Authentication Software | 8.5 (#8) | 7.9 (#15) |
| Integrations | Clerk documents integrations with Convex, Firebase, Supabase, Shopify, Vercel Marketplace, and Google Analytics. | The maker documents React, Express, Fastify, and Next.js integrations, with a framework-agnostic core for other runtimes. |
| Product | Clerk provides full-stack authentication and user management, including Organizations and Billing. | Seamless Auth is open-source passwordless authentication infrastructure that can be self-hosted or used as a managed service. |
Plans
Seamless Auth
- Free trialFree
- MVP$49 a month
- Business$149 a month
- EnterprisePriced on request
In their own words
Clerk
Clerk provides full-stack authentication and user management for applications, including Organizations and Billing. Prebuilt components cover sign-up, sign-in, and user profiles, while Frontend, Backend, and Platform HTTP APIs support client-side, backend, and workspace operations. Clerk Billing handles subscription billing and charges 0.7% of billing volume in addition to Stripe fees. Its free B2B offering includes 100 monthly retained organizations per app and up to 20 members per Organization. Listed integrations include Convex, Firebase, Supabase, Shopify, Vercel Marketplace, and Google Analytics. Security practices include account lockout, bot protection, rate limiting, breached-password detection, and MFA enforcement. Clerk lists SOC 2 Type 2 and HIPAA certifications; SOC 2 reports are available on Business and above, while a HIPAA BAA is available on Enterprise. Data is hosted on US infrastructure, with no regional data residency. Clerk is available on Android, iOS, web, APIs, and extensions, and provides an iOS SDK for native Apple apps. Hobby is free; Pro costs $20/mo billed annually, and Business costs $250 per year billed annually.
Seamless Auth
Seamless Auth has no write-up on Specifiction yet; its figures are above.