Auth0 vs Fly.io
Customer identity platform from Okta
vs. Run your app close to users, globally
Pricing tiers
Auth0
B2C Essentials
Starting at 500 MAUs. Pro MFA, RBAC, passwordless, SAML, 10 orgs.
$35/mo
B2B Essentials
Unlimited orgs, 3 SSO connections, RBAC.
$150/mo
B2C Professional
Starting at 500 MAUs. Includes attack protection, custom DB, enterprise MFA.
$240/mo
B2B Professional
5+ SSO connections, attack protection, custom DB.
$800/mo
Enterprise
Custom. 99.99% SLA, dedicated support.
Custom
Fly.io
Pay-as-you-go
No monthly fee. Machines billed per second. Free allocations: ~3 small shared machines + 3 GB volumes.
$0 base (usage-based)
Shared CPU 1x — 256 MB
Entry VM. 1 shared vCPU, 256 MB RAM. ~$2.02/month continuously on.
$2/mo
Performance 1x — 2 GB
Dedicated 1 vCPU, 2 GB RAM.
$32/mo
Reservation — Shared (1 yr)
$36/year for $5/mo credit (40% savings).
$36/mo
Shared CPU 8x — 16 GB
8 shared vCPU, 16 GB RAM.
$89/mo
Performance 16x — 128 GB
Dedicated 16 vCPU, 128 GB RAM.
$1014/mo
Enterprise
Custom. Dedicated capacity, SLA.
Custom
Free-tier quotas head-to-head
Comparing b2c-essentials on Auth0 vs pay-as-you-go on Fly.io.
| Metric | Auth0 | Fly.io |
|---|---|---|
| mau start | 500 MAU | — |
| sso connections | 0 conns | — |
Features
Auth0 · 14 features
- Attack Protection — Bot detection, brute-force protection, breached-password detection, suspicious I…
- Auth0 Actions — Node.js + TS hooks that run during auth flows (login, post-login, signup, MFA). …
- Auth0 FGA (OpenFGA) — Fine-grained relationship-based authorization (ReBAC). Based on Google Zanzibar.
- Custom Database — BYO user DB: scripts in Actions read from your database and create Auth0 users o…
- Custom Domain — Serve auth at auth.yourbrand.com with managed cert.
- Enterprise SSO — SAML 2.0 + OIDC + AD/LDAP enterprise connections. Per-tenant or per-org.
- Log Streaming — Stream tenant logs to Datadog, Splunk, Sumo Logic, Azure Sentinel, HTTP, Mixpane…
- Machine-to-Machine — Client-credentials grant for backend services.
- Multi-Factor Auth — SMS, Voice, Email, TOTP, WebAuthn (biometrics), Push (Guardian app), Duo.
- Organizations — Multi-tenant B2B: orgs with invitations, roles, branding, enterprise connections…
- Passkeys — FIDO2/WebAuthn passkey sign-in.
- Passwordless — Email magic link + code, SMS code, WebAuthn.
- RBAC — Roles, permissions, API scopes — attach to users or orgs.
- Universal Login — Hosted login page with customization, multi-factor flows, passwordless, social, …
Fly.io · 14 features
- Auto Stop/Start — Machines auto-stop when idle, start on request (like scale-to-zero).
- Certs — Let's Encrypt + wildcard certs managed.
- Fly GPU — A100/L40S/A10 on-demand GPU machines.
- Fly Kubernetes (FKS) — Managed Kubernetes on Fly machines.
- Fly Machines — Firecracker microVMs. Start in <1s. Run any Docker image.
- Fly Postgres — Managed Postgres via Supabase partnership (2024). Also legacy self-run Postgres …
- fly-replay headers — Route request to another region at app level.
- Fly Volumes — Persistent SSD attached to a Machine. Encrypted at rest.
- Global Anycast — Single IP routes to the closest region automatically.
- LiteFS — Distributed SQLite with primary/replica across regions.
- Private Networks — 6PN WireGuard mesh. Connect machines across regions privately.
- Secrets — Encrypted env vars propagated to all regions.
- Tigris (partner) — S3-compatible storage for Fly apps. By partner.
- Upstash Redis (partner) — Managed Redis via Upstash.
Developer interfaces
| Kind | Auth0 | Fly.io |
|---|---|---|
| CLI | Auth0 CLI | flyctl CLI |
| SDK | Auth0 Android, Auth0 iOS/Swift, @auth0/nextjs-auth0, Auth0 React SDK, Auth0 SPA.js SDK, Go Auth0 SDK, Node Auth0 Backend SDK, Python Auth0 SDK | — |
| REST | Authentication API, Management API | Machines API |
| GRAPHQL | — | Fly GraphQL API |
| OTHER | — | Fly Postgres (wire) |
Staxly is an independent catalog of developer platforms. Outbound links to Auth0 and Fly.io are plain references to their official websites. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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