アーキテクチャ・意思決定比較表
Clerk と Supabase のデータ構造、運用コスト、ライセンスリスクの違いを詳細に分析します。
While Clerk offers an incredibly friction-free developer experience for user authentication, its usage-based pricing model can quickly escalate into a significant financial burden as your active user base scales. For financial planners and engineering leads aiming to control long-term operational expenditures, evaluating the total cost of ownership (TCO) of Clerk against a robust open-source alternative like Supabase is critical for strategic engineering decisions.
Clerk Official Plans & Pricing (2026)
Below is the official breakdown of Clerk’s pricing tiers, designed to scale from early-stage MVPs to enterprise-grade deployments.
| Plan | Price (Monthly) | Price (Annualized Monthly) | Key Highlights & Inclusions | Target Audience |
|---|---|---|---|---|
| Free | $0 | $0 | Up to 10,000 Monthly Active Users (MAUs), unlimited social logins, standard authentication features. | Side projects, hobbyists, and early-stage validation. |
| Growth | $25 / project | $25 / project | Includes 10,000 MAUs, custom domains, advanced MFA, organization membership & multi-tenancy. | Growing startups and B2B SaaS applications requiring basic multi-tenancy. |
| Enterprise | Custom | Custom | SAML/OIDC SSO, custom session lengths, dedicated support, custom SLAs. | Mid-market to large enterprises requiring strict compliance and corporate SSO. |
The Hidden Costs of Clerk
Evaluating clerk pricing solely on the flat monthly fees can lead to unexpected budget overruns. Several hidden costs and structural pricing escalations exist:
- High-Volume MAU Overages: Once your application surpasses the 10,000 MAU threshold included in the Free and Growth tiers, Clerk bills overages at $0.02 per additional MAU. For a consumer-facing app scaling to 100,000 MAUs, this introduces an unpredicted monthly overage of $1,800.
- Telephony & SMS MFA Fees: SMS-based Multi-Factor Authentication (MFA) and One-Time Passwords (OTP) are not covered by the flat fee. Delivery rates vary significantly by destination country and carrier fees, which can quickly inflate the clerk cost if SMS is your primary verification channel.
- The “SAML Tax” (Enterprise Gatekeeping): If you are building B2B software, your enterprise customers will eventually demand SAML/OIDC SSO. Clerk restricts these features to the Enterprise tier, forcing teams off the $25/month Growth plan and onto custom contracts that typically require significant annual financial commitments.
- Administrative Seat Licenses: While developer seats are generally flexible, advanced organizational management and collaboration features within the Clerk dashboard can carry additional per-seat costs at the enterprise level.
Total Cost of Ownership (TCO) Analysis: Supabase Self-Host
Supabase stands out as the premier clerk free alternative. As an Apache-2.0 open-source backend-as-a-service, it bundles a powerful Postgres-native authentication system. However, self-hosting Supabase is not entirely “free”—it shifts costs from software licenses to cloud infrastructure and engineering hours.
Cost Trade-offs at a Glance
1. Hosting & Server Resource Estimation
- Small Team (Low Traffic / Dev): Running Supabase Auth (GoTrue) and Postgres on a single shared VPS (e.g., AWS EC2 t4g.small or DigitalOcean Droplet).
- Cost: ~$15 - $30/month.
- Medium Team (Production Scale, ~50k MAUs): Multi-instance deployment with High Availability (HA) Postgres, separate authentication containers, and a Redis cache layer for session management.
- Cost: ~$150 - $350/month.
- Large Team (Enterprise Scale, 500k+ MAUs): Multi-region, auto-scaling Kubernetes clusters with dedicated, clustered Postgres databases, automated backups, and advanced network security (WAF/DDoS protection).
- Cost: ~$1,200 - $2,500/month.
2. Maintenance & Engineering Support Estimation
Self-hosting means your engineering team becomes the Reliability Engineers (SREs).
- Small Team: ~2 hours/month for basic security patches and Docker updates. (Estimated internal cost: ~$150/month).
- Medium Team: ~10 hours/month for database tuning, backup verification, and minor upgrades. (Estimated internal cost: ~$800/month).
- Large Team: Dedicated DevOps attention (~30 hours/month) for handling scaling issues, high-availability testing, and compliance documentation. (Estimated internal cost: ~$3,000/month).
Comparative TCO Table: Clerk SaaS vs. Supabase Self-Hosted
| Cost Category | Clerk SaaS (Scale-Up / Enterprise) | Supabase (Self-Hosted) |
|---|---|---|
| Licensing / Software Fees | $25/mo + $0.02 per MAU overage (or Custom Enterprise) | $0 (Open-Source Apache-2.0) |
| Compute / Database Infra | Included | $15 to $2,500+/mo (depending on scale) |
| SMS/MFA Delivery Costs | Passed through (carrier rates apply) | Passed through (via your own Twilio/Sinfon integration) |
| Internal Maintenance Labor | Minimal (SDK integration only) | $150 to $3,000+/mo (Engineering overhead) |
| Enterprise SSO (SAML) | High cost (requires Enterprise tier negotiation) | Included free (configured via Supabase Auth) |
Cost Scenarios for Engineering Teams
To ground these numbers, let us analyze three concrete scenarios based on engineering team sizes and active user scales.
Scenario A: 5-Developer Team (Early-Stage Startup, 8,000 MAUs)
- Clerk Cost: $25/month. The team fits comfortably inside the Growth tier.
- Supabase Self-Host Cost: ~$15/month (Infra) + $150/month (Developer opportunity cost to maintain) = $165/month.
- Financial Decision: Clerk Wins. At this scale, paying the nominal $25/month keeps your engineers focused entirely on building core product features rather than managing authentication infrastructure.
Scenario B: 20-Developer Team (Scale-Up, 80,000 MAUs)
- Clerk Cost: $25 base + $1,400 overage (70,000 excess MAUs * $0.02) = $1,425/month.
- Supabase Self-Host Cost: ~$250/month (Reliable HA Infra) + $800/month (Maintenance labor) = $1,050/month.
- Financial Decision: Toss-Up. While Supabase self-hosting is technically cheaper on paper, the margin is narrow enough that the convenience, pre-built UI components, and peace of mind provided by Clerk’s fully managed SaaS could still justify the premium.
Scenario C: 100-Developer Enterprise (Large-Scale SaaS, 500,000 MAUs + SAML SSO)
- Clerk Cost: Locked into custom Enterprise pricing. Based on industry benchmarks for 500k MAUs and enterprise features, this typically ranges between $6,000 to $12,000+/month under annual contracts.
- Supabase Self-Host Cost: ~$1,500/month (Multi-region Kubernetes + DB cluster) + $3,000/month (Dedicated DevOps engineering fraction) = $4,500/month.
- Financial Decision: Supabase Wins Decisively. At enterprise scale, the “SAML tax” combined with massive MAU overages makes Clerk exceptionally expensive. Self-hosting Supabase provides complete data sovereignty, custom database control, and massive cost savings.
When Does Paying for Clerk Actually Save Money?
Despite the higher price ceiling, opting for Clerk is the financially superior option under the following conditions:
- Speed-to-Market is the Top Priority: If your engineering team needs to launch a prototype or MVP in days rather than weeks, Clerk’s pre-built UI components (e.g.,
<SignIn />,<UserProfile />) save hundreds of hours of frontend development. - Zero DevOps Capability: If your team consists entirely of frontend or product engineers with no dedicated backend or database administration expertise, self-hosting a production-grade database and auth server introduces massive operational risk.
- Complex Multi-Tenancy Requirements Out-of-the-Box: Clerk’s “Organizations” feature simplifies B2B seat management, invitation flows, and role-based access control (RBAC) with minimal custom backend code.
Final Purchasing Recommendation
- Choose Clerk if: You are an early-stage team, a product-led growth (PLG) startup with under 20,000 MAUs, or a team without deep systems-engineering resources. The time-to-market advantages and polished UI components more than justify the initial subscription cost.
- Choose Supabase (Self-Hosted) if: You are scaling rapidly past 50,000 MAUs, require custom database schemas directly coupled with your auth layer, or must support B2B Enterprise SAML SSO without paying premium SaaS taxations. The long-term infrastructure and operational cost savings will easily offset the engineering maintenance overhead.
Cost and pricing analysis verified as of 2026-06-25. Self-hosting costs are estimates based on standard cloud providers.
よくある質問
What hidden costs should I expect when scaling past Clerk's 10,000 free MAUs compared to using Supabase?
Once you exceed Clerk's free tier, overages are billed at $0.02 per additional monthly active user (MAU), and you must pay $25 per project/month to unlock custom domains and advanced MFA on the Growth plan. Additionally, Clerk charges variable carrier fees for SMS-based MFA and OTP messages depending on the destination country. With Supabase, you can self-host their Apache-2.0 licensed, TypeScript-based authentication stack on your own infrastructure to bypass these per-user and per-message scaling costs entirely.
How do Clerk and Supabase differ in pricing for B2B multi-tenancy and enterprise SSO integrations?
Clerk packages B2B organization memberships and multi-tenancy into its $25/month Growth plan, but requires a custom-priced Enterprise contract for SAML/OIDC SSO and custom session lengths. In contrast, Supabase's core authentication engine is open-source under the Apache-2.0 license, meaning you can deploy and configure enterprise auth features without getting locked into a custom SaaS contract. This makes Supabase's TypeScript-based stack a highly flexible option for self-hosting B2B architectures.
機能と価格データは公式ドキュメントと料金ページを出典としており、最終確認日は 2026年6月25日 です。 誤りを見つけましたか?お知らせいただければ修正します。