📡 hetzner-server-radar

Out-of-stock radar for Hetzner Cloud — watch · match · email

Polls the Hetzner Cloud API for a given server type in a given location and emails you the moment it comes back in stock. A single-file Node script — point it at a CX/CCX/CAX type and a datacenter, run it, and walk away.

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• Explore — What it is · Quick start · Configuration · How it works · Tech stack · Docs

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What it is

hetzner-server-radar is a small watcher for Hetzner Cloud capacity. Popular server types (especially the dedicated CCX line and the cheap CX/CAX types) routinely sell out in specific datacenters; this tool polls the public datacenter API on a fixed cadence and sends an email alert the moment your chosen type is available where you want it.

Defaults: CX33 (id 115) in Nuremberg (nbg1), checking every 5 minutes. Everything is configurable via .env. While a type stays available the tool stays quiet — it alerts on the transition into stock, then waits out a cooldown before it can fire again, so you get a heads-up rather than a flood.

Quick start

Requires Node 22 (see .nvmrc).

nvm use            # picks up .nvmrc
npm install
cp .env.example .env
# edit .env: fill in HCLOUD_TOKEN, RESEND_API_KEY, ALERT_EMAIL_TO
npm start

Script	What it does
npm start	run the radar (tsx src/index.ts)
npm run dev	run with file-watch reload
npm run typecheck	tsc --noEmit

Stop with Ctrl-C.

Configuration

All settings come from .env — copy .env.example and fill in the three required secrets.

Var	Required	Default	Notes
HCLOUD_TOKEN	yes	—	Hetzner Cloud API token; read scope is enough
RESEND_API_KEY	yes	—	from https://resend.com
ALERT_EMAIL_TO	yes	—	alert recipient
SERVER_TYPE_ID	no	115 (CX33)	Hetzner server type id
LOCATION_PREFIX	no	nbg1 (Nuremberg)	matched against dc.name.startsWith(...)
CHECK_INTERVAL_SECONDS	no	300	poll cadence in seconds
EMAIL_COOLDOWN_SECONDS	no	3600	min seconds before a new alert can fire; suppresses flapping
HETZNER_PROJECT_ID	no	—	when set, the "Buy now" link deep-links to that project's create-server page (find it in the console URL: https://console.hetzner.cloud/projects/<id>/...)

LOCATION_PREFIX options

Matched with dc.name.startsWith(...), so use a location name (or a specific datacenter name for finer scope). Verified against GET /v1/datacenters on 2026-05-10.

Prefix	City	Country	Datacenter
nbg1	Nuremberg	DE	nbg1-dc3
fsn1	Falkenstein	DE	fsn1-dc14
hel1	Helsinki	FI	hel1-dc2
ash	Ashburn, VA	US	ash-dc1
hil	Hillsboro, OR	US	hil-dc1
sin	Singapore	SG	sin-dc1

SERVER_TYPE_ID options

All active server types from GET /v1/server_types (verified 2026-05-10). Specs are cores / memory GB / disk GB.

ID	Name	Specs	CPU	Arch
22	cpx11	2 / 2 / 40	shared	x86
23	cpx21	3 / 4 / 80	shared	x86
24	cpx31	4 / 8 / 160	shared	x86
25	cpx41	8 / 16 / 240	shared	x86
26	cpx51	16 / 32 / 360	shared	x86
45	cax11	2 / 4 / 40	shared	arm
93	cax21	4 / 8 / 80	shared	arm
94	cax31	8 / 16 / 160	shared	arm
95	cax41	16 / 32 / 320	shared	arm
96	ccx13	2 / 8 / 80	dedicated	x86
97	ccx23	4 / 16 / 160	dedicated	x86
98	ccx33	8 / 32 / 240	dedicated	x86
99	ccx43	16 / 64 / 360	dedicated	x86
100	ccx53	32 / 128 / 600	dedicated	x86
101	ccx63	48 / 192 / 960	dedicated	x86
108	cpx12	1 / 2 / 40	shared	x86
109	cpx22	2 / 4 / 80	shared	x86
110	cpx32	4 / 8 / 160	shared	x86
111	cpx42	8 / 16 / 320	shared	x86
112	cpx52	12 / 24 / 480	shared	x86
113	cpx62	16 / 32 / 640	shared	x86
114	cx23	2 / 4 / 40	shared	x86
115	cx33	4 / 8 / 80	shared	x86
116	cx43	8 / 16 / 160	shared	x86
117	cx53	16 / 32 / 320	shared	x86

93–95, 116, 117 are listed by the API but not in any datacenter's available list at the time of verification — pick one of these only if you're specifically waiting for it to come back in stock.

How it works

src/index.ts calls GET https://api.hetzner.cloud/v1/datacenters every CHECK_INTERVAL_SECONDS, keeps datacenters whose name starts with LOCATION_PREFIX, and checks whether their server_types.available list contains SERVER_TYPE_ID.

flowchart LR
  Timer["⏱️ poll loop"] --> DC["Hetzner /v1/datacenters"]
  DC --> Filter["filter by LOCATION_PREFIX\n+ SERVER_TYPE_ID available"]
  Filter -- "match (newly in stock)" --> Resend["Resend email alert"]
  Filter -- "no match / cooldown" --> Timer
  Resend --> Inbox["📬 your inbox"]

Loading

On a transition into "available" it sends an alert email through Resend (subject + plaintext/HTML body, with an optional "Buy now" deep-link). It does not re-alert every cycle while the type stays in stock; once it drops out and comes back, a new alert can fire after EMAIL_COOLDOWN_SECONDS has elapsed.

Tech stack

Layer	Tech
Runtime	Node 22 (ESM), run via tsx
Language	TypeScript 6 (strict, noEmit typecheck)
Data source	Hetzner Cloud public API (/v1/datacenters, /v1/server_types, /v1/locations)
Email	Resend
Config	dotenv (.env)

Docs & decisions

This is a single-file utility — the full behavior lives in src/index.ts and the configuration reference above. There is no separate docs/ tree.

Not yet present in this repo: a LICENSE file, a CI workflow (.github/workflows/), and a docs/ directory. Add these if the project grows beyond a single script.