Fly.io vs Calendly
Run your app close to users, globally
vs. The scheduling category leader — dominant polished SaaS booking tool
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
Calendly
Free
$0. 1 user. 1 event type. Unlimited 1-on-1 meetings. Basic calendar integrations.
Free
Standard
$12/user/mo. Unlimited event types. Group events. Remove branding. 7 integrations.
$12/mo
Teams
$20/user/mo. Round-robin, collective, Salesforce/HubSpot, Zapier, routing, metrics.
$20/mo
Enterprise
Starts ~$15,000/year (5-10 users). SSO, SCIM, advanced routing, dedicated success manager, SLA.
$15000/mo
Free-tier quotas head-to-head
Comparing pay-as-you-go on Fly.io vs free on Calendly.
| Metric | Fly.io | Calendly |
|---|---|---|
| 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.
Calendly · 16 features
- Admin Management — Centralized team billing + controls.
- Analytics — Team conversion + activity.
- Availability — Schedules + recurring hours.
- Buffers — Before/after meetings.
- Daily / Weekly Limits — Cap bookings.
- Event Types — One-off, group, collective, round-robin.
- HubSpot Integration — Native sync.
- Inline + Popup Embed — Widget for websites.
- Marketing Routing — Form-based routing to teams/reps.
- Meeting Polls — Group availability poll (like When2Meet).
- Paid Bookings — Stripe integration.
- Round-Robin — Distribute across team.
- Salesforce Integration — Native, deep sync (Teams+).
- SSO — Enterprise only.
- Webhooks — Real-time events.
- Workflows — Automated reminders + follow-ups.
Developer interfaces
| Kind | Fly.io | Calendly |
|---|---|---|
| CLI | flyctl CLI | — |
| REST | Machines API | Calendly REST API |
| GRAPHQL | Fly GraphQL API | — |
| OTHER | Fly Postgres (wire) | Calendly App, Calendly Embed Script, Calendly Webhooks, Chrome Extension, Zapier Integration |
Staxly is an independent catalog of developer platforms. Some links to Fly.io and Calendly 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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