At 50k users and 5 SSO connections, verified plans differ by up to $11,700 a year.
AuthCost shows what auth actually costs — base plan, MAU/MRU overage, and enterprise SSO fees — so you pick the cheaper stack and hear when it changes.
Free · no signup · no card. Prices from official pages only.
- Source-linked every price links the vendor’s own page
- Independent no vendor pays for placement
- Checked weekly a script diffs every source page
- No paid rankings ordered by computed cost only
As of 2026-10-30, from 19 verified plan rows. Gaps use verified rows only; plans that cannot price the scenario are omitted. How we calculate this.
Auth bills hide in the unit.
MAU vs MRU
Clerk’s MRU skips one-day users. Comparing it to Auth0 MAU without adjusting understates or overstates the gap.
Per-connection SSO
WorkOS and Stytch charge per enterprise connection ($125 entry). Clerk includes one on Pro then $75. Kinde Plus includes unlimited SSO in the base.
Silent fee starts
Clerk Directory Sync billing begins 2027-01-01 — logged in our price log before it hits invoices.
The ledger
Monthly USD list prices. Sorted by base fee; use the calculator for your MAU + SSO scenario.
| Vendor | Plan | Base / mo | Included users | Unit | Overage | SSO incl. | SSO extra | Status | Source · checked |
|---|---|---|---|---|---|---|---|---|---|
| Clerk | Hobby | $0 | 50000 | MRU | — | 0 | — | Verified | source · 2026-10-30 |
| Clerk | Pro | $25 $20 annual | 50000 | MRU | $0.0200 | 1 | $75 | Verified | source · 2026-10-30 |
| Clerk | Business | $300 $250 annual | 50000 | MRU | $0.0200 | 1 | $75 | Verified | source · 2026-10-30 |
| Auth0 | Free | $0 | 25000 | MAU | — | 1 | — | Verified | source · 2026-10-30 |
| Auth0 | Essentials (B2C) | $35 | 500 | MAU | — | — | — | Verified | source · 2026-10-30 |
| Auth0 | Professional (B2C) | $240 | 500 | MAU | — | — | — | Verified | source · 2026-10-30 |
| Amazon Cognito | Lite | $0 | 10000 | MAU | $0.0055 | — | — | Verified | source · 2026-10-30 |
| Amazon Cognito | Essentials | $0 | 10000 | MAU | $0.0150 | — | — | Verified | source · 2026-10-30 |
| Amazon Cognito | Plus | $0 | 0 | MAU | $0.0200 | — | — | Verified | source · 2026-10-30 |
| WorkOS | AuthKit | $0 | 1000000 | MAU | $2500/1M | 0 | $125 | Verified | source · 2026-10-30 |
| Stytch | Pay as you go (B2B) | $0 | 10000 | MAU | — | 5 | $125 | Verified | source · 2026-10-30 |
| Logto | Free | $0 | 50000 | MAU | — | 0 | — | Verified | source · 2026-10-30 |
| Logto | Pro | $24 | — | token | — | 0 | $48 | Verified | source · 2026-10-30 |
| Kinde | Free | $0 | 10500 | MAU | — | 1 | — | Verified | source · 2026-10-30 |
| Kinde | Pro | $25 | 10500 | MAU | $0.0175 | 1 | — | Verified | source · 2026-10-30 |
| Kinde | Plus | $75 | 10500 | MAU | $0.0163 | ∞ | $0 | Verified | source · 2026-10-30 |
| Kinde | Scale | $250 | 10500 | MAU | $0.0151 | ∞ | $0 | Verified | source · 2026-10-30 |
| Supabase Auth | Free (platform) | $0 | 50000 | MAU | — | 0 | — | Verified | source · 2026-10-30 |
| Supabase Auth | Pro (platform) | $25 | 100000 | MAU | $0.0032 | — | — | Verified | source · 2026-10-30 |
Know the week an auth price changes
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Questions
What does AuthCost compare?
Published list prices for auth and identity vendors: base plan fees, MAU/MRU allowances and overages, and enterprise SSO / Directory Sync connection fees. Every row links the vendor’s own pricing page and the date we checked it.
MAU vs MRU — why does it matter?
Most vendors bill Monthly Active Users (any activity that month). Clerk bills Monthly Retained Users — a user who returns at least one day after signup. MRU is often lower than MAU for apps with many one-time signups, so a raw MAU-to-MAU comparison understates Clerk’s relative price.
Why are some rows blank?
We never invent a number. If a rate is “contact sales,” custom, or not printed as a fixed figure on the official page, we leave it blank and mark the gap.
How is the calculator’s cost computed?
Monthly ≈ base + max(0, users − included) × overage + SSO fees from the published ladder + verified MFA add-ons when MFA is required. Cognito/Supabase SAML uses a federated-MAU assumption you can change. Token-based plans (Logto) use base + SSO (+ MFA add-on if required) only unless noted. We never invent an MFA price.
Do affiliate links change rankings?
No. Ranking is by computed cost only. Affiliate links are labeled when active.