Fly.io vs Cal.com
Run your app close to users, globally
vs. Open-source scheduling infrastructure — the self-hostable Calendly alternative
Pricing tiers
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
Cal.com
Free (Cloud)
$0. 1 user. Unlimited event types. Unlimited meetings. Cal branding.
Free
Self-Hosted (OSS)
Free forever. AGPL-3.0. Docker/K8s deploy. Full feature parity with cloud.
$0 base (usage-based)
Teams
$12/user/mo. Round-robin, collective events, routing forms, Cal Video, Workflows.
$12/mo
Organizations
$37/user/mo. SSO, advanced routing, dashboards, analytics, dedicated support.
$37/mo
Enterprise
Custom. SAML, HIPAA, dedicated deployments, security reviews.
Custom
Free-tier quotas head-to-head
Comparing pay-as-you-go on Fly.io vs free on Cal.com.
| Metric | Fly.io | Cal.com |
|---|---|---|
| No overlapping quota metrics for these tiers. | ||
Features
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.
Cal.com · 16 features
- Availability — Multiple schedules per user.
- Buffer Time — Padding between meetings.
- Cal Video — Built-in video conferencing.
- Embed — Inline/popup/floating-button embeds.
- Event Types — One-on-one, group, collective, round-robin.
- Insights Dashboard — Booking trends + team analytics.
- Paid Bookings — Stripe integration for paid appointments.
- Platform API — Embed scheduling in your SaaS.
- Recurring Events — Weekly/monthly recurring bookings.
- Round-Robin — Distribute bookings across team.
- Routing Forms — Route leads by answers.
- Self-Host — Deploy to your infra.
- SSO — SAML + OIDC.
- Timezone Detection — Auto-detect viewer timezone.
- Webhooks — Outbound events.
- Workflows — Automated email/SMS reminders.
Developer interfaces
| Kind | Fly.io | Cal.com |
|---|---|---|
| CLI | flyctl CLI | cal CLI (self-host) |
| SDK | — | @calcom/embed-react |
| REST | Machines API | Cal.com REST API v2, Platform API (embed in SaaS) |
| GRAPHQL | Fly GraphQL API | — |
| OTHER | Fly Postgres (wire) | Cal.com Dashboard, Cal.com Webhooks |
Staxly is an independent catalog of developer platforms. Some links to Fly.io and Cal.com may be affiliate links — Staxly may earn a commission if you sign up through them, at no extra cost to you. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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