Compare / Unkey vs Fly.io Machines
Unkey vs Fly.io Machines
Pre-calculated from hand-checked data — Unkey checked 2026-08-06, Fly.io checked 2026-08-06.
The short version
Fly.io Machines wins more of our comparison points, but Unkey still fits if production APIs that want hosting, gateway policies, API keys, rate limits, and request analytics in one place describes you.
Price Fly.io Machines
Fly.io Machines is cheaper at every stage we model — about $12/mo even for a growing project.
Ease Unkey
Unkey is easier to get running: connect GitHub for automatic builds and branch previews, or deploy a Docker image from the Unkey CLI.
Control Fly.io Machines
Fly.io Machines gives you more control over the stack — the flip side of the convenience trade.
Features Fly.io Machines
Fly.io Machines comes out ahead on 5 of the 15 features we track, versus 3.
What developers say about this matchup
We couldn't find a substantive first-person discussion comparing this exact pair. We leave the section empty instead of filling it with vendor marketing or generic SEO comparisons.
At a glance
| Unkey | Fly.io Machines | |
|---|---|---|
| Best for | Production APIs that want hosting, gateway policies, API keys, rate limits, and request analytics in one place. | Dockerized apps that want low cost, fine control, or multi-region placement. |
| How deploys work | Connect GitHub for automatic builds and branch previews, or deploy a Docker image from the Unkey CLI. | fly launch builds the image and deploys it; configuration lives in fly.toml and the flyctl CLI. |
| The tradeoff | It is a young, API-specific platform with metered billing, ephemeral storage, and no managed database. | You operate more of the stack yourself — especially the database. |
| Free tier | None | None |
What you'd realistically pay
Unkey Fly.io Machines
| Project stage | Unkey | Fly.io Machines | Cheaper |
|---|---|---|---|
| Just starting | ≈$5/mo Starter — The $5 minimum includes $5 of usage, enough for a small, lightly used API. | ≈$3/mo shared-cpu-1x, 256 MB — About $2.02/month in Amsterdam if always on; less with scale-to-zero. | Fly.io Machines |
| Steady traffic | ≈$18/mo Starter + usage — About 0.5 active vCPU and 1 GB of memory running continuously before egress or active-key charges. | ≈$6/mo shared-cpu-1x, 1 GB — About $5.92/month in Amsterdam, plus egress at $0.02/GB. | Fly.io Machines |
| Growing | ≈$50/mo Business — The $50 minimum becomes usage credit and raises per-instance limits to 16 vCPU and 32 GB of RAM. | ≈$12/mo Two 1 GB Machines — Two machines for availability; databases and egress on top. | Fly.io Machines |
Unkey pricing notes
- Usage rates are $0.000006944 per vCPU-second, $0.000003472 per GB-second of memory, $0.00000006 per GB-second of ephemeral disk, and $0.05 per GB of egress.
- API-key authentication through the gateway adds $0.002 per active key each month. The plan minimum is included usage credit rather than an extra charge on top.
- Log retention is 3 days on Starter, 7 days on Pro, and 14 days on Business.
Fly.io Machines pricing notes
- Billed per second only while Machines are started; scale-to-zero is natively supported.
- Egress: $0.02/GB in North America and Europe; more elsewhere.
Our ratings
Ease of use Unkey
Pricing clarity Unkey
Free tier
Scaling Unkey
Control Fly.io Machines
Feature by feature
Unkey wins 3, Fly.io Machines wins 5, with 7 even.
Deploy workflow
| Unkey | Fly.io Machines | |
|---|---|---|
| Deploy from Git push | Yes Connect GitHub; pushes to the default branch deploy production automatically. | Partial No native git integration; the documented path is flyctl in GitHub Actions. |
| Preview deploys | Yes Non-default branches and pull requests receive isolated preview deployments. | Partial PR apps work via the official GitHub Action, not out of the box. |
| Official CLI | Yes The Unkey CLI deploys local build contexts or pre-built container images. | Yes flyctl does everything: launch, deploy, scale, ssh, logs. |
| Instant rollbacks | Yes Rollbacks atomically switch traffic to a previous immutable deployment. | Partial Redeploy any previous image; no one-click dashboard rollback. |
Platform
| Unkey | Fly.io Machines | |
|---|---|---|
| Custom domains + HTTPS | Yes Custom apex domains and subdomains include automatic TLS; plan limits apply. | Yes Custom domains with free managed certificates. |
| Built-in CDN / edge network | No The global gateway routes API traffic but is not a static-asset caching CDN. | Partial Anycast routing sends users to the nearest region, but there is no static-asset CDN. |
| Serverless functions | No Applications run as container instances rather than per-request functions. | No Machines are micro-VMs, not functions. |
| Docker containers | Yes Build from a Dockerfile or deploy a pre-built image from a registry. | Yes A Docker image is the deployment unit. |
| SSH / shell access | No The documented workflow exposes logs and metrics, not an interactive SSH shell. | Yes fly ssh console opens a shell in any running Machine. |
| EU hosting region | Yes European deployment regions are available; Starter includes three regions and paid upgrades unlock all. | Yes Amsterdam, Paris, Frankfurt, London, and more. |
Runtime & operations
| Unkey | Fly.io Machines | |
|---|---|---|
| Automatic scaling | Yes Horizontal autoscaling adjusts instance count from configured minimums and maximums based on CPU load. | Yes Machines autostart and autostop with traffic; scale counts per region. |
| Scale to zero | Partial Preview environments sleep automatically when idle; apps can also be stopped and started manually. | Yes Stopped Machines cost only their storage. |
| Scheduled jobs | No There is no documented first-class scheduler for cron jobs. | Partial Scheduled Machines run on fixed intervals; full cron needs a workaround. |
| Managed database | No No managed database is included; connect an external database service. | Partial Fly Postgres is automated-but-unmanaged; managed options come from partners like Supabase and Upstash. |
| Logs & metrics built in | Yes Runtime logs, CPU and memory metrics, request analytics, and gateway decisions appear in the dashboard. | Yes Built-in metrics (Grafana), live logs, and log shipping. |
Watch out for
Unkey
- Unkey only launched public app hosting in 2026, so its production track record is much shorter than established platforms such as Heroku, Render, or Railway.
- The monthly plan price is a minimum with matching usage credit, not a compute bundle: CPU, memory, ephemeral disk, egress, and active keys are metered separately.
- Storage is ephemeral and there is no managed database, so persistent data must live with another provider.
Fly.io
- New pay-as-you-go organizations get no free allowance.
- Fly Postgres is explicitly unmanaged: automated but not a managed database service — backups and failover are your responsibility.
- Per-second compute plus $0.02/GB egress makes bills variable; prices differ by region.
Read the full reviews: Unkey and Fly.io. Or answer four questions to see what fits your project.