Fly.io vs Retool
Run your app close to users, globally
vs. The low-code platform for internal tools, workflows, and AI agents
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
Retool
Free
$0. Up to 5 users. Unlimited apps + mobile. 500 workflow runs/month. 5GB DB + storage. 20 hrs/mo Agents.
Free
Team
$10/builder/mo + $5/internal user/mo. 5k workflow runs. Staging env. App releases.
$10/mo
Business
$50/builder/mo + $15/internal user/mo. Audit logs, rich permissions, portals, embedded apps, external user pricing.
$50/mo
Enterprise
Custom. SAML/OIDC SSO, source control, error monitoring, full white-labeling, volume discounts.
Custom
Free-tier quotas head-to-head
Comparing pay-as-you-go on Fly.io vs free on Retool.
| Metric | Fly.io | Retool |
|---|---|---|
| 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.
Retool · 14 features
- Apps (Web + Mobile) — Drag-drop UI builder with 100+ components.
- Audit Logs — Track every user action.
- Custom JavaScript — Write JS anywhere in app logic.
- MCP Support — Expose Retool workflows to AI agents.
- Modules — Reusable component bundles.
- Retool Agents — AI agents that use Retool queries + apps as tools.
- Retool Database — Managed Postgres with GUI + collab.
- Retool Embed — Embed apps into your SaaS.
- Retool Forms — Public forms that write to DBs.
- Retool Portals — External-facing apps for customers.
- SAML/OIDC SSO (Ent) — Enterprise auth.
- Source Control (Ent) — Git-backed version control for apps.
- White-labeling (Ent) — Full brand customization.
- Workflows — Cron + webhook-triggered automations with branching.
Developer interfaces
| Kind | Fly.io | Retool |
|---|---|---|
| CLI | flyctl CLI | — |
| REST | Machines API | Retool REST API (Workflows) |
| GRAPHQL | Fly GraphQL API | — |
| MCP | — | Retool MCP |
| OTHER | Fly Postgres (wire) | Retool Database, Retool Editor, Self-Hosted (on-prem) |
Staxly is an independent catalog of developer platforms. Outbound links to Fly.io and Retool are plain references to their official websites. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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