Homelab Hardware Sizing Tool
Last checked: 2026-10-25. Every figure below is quoted from the app's official documentation (linked, with the version we pin on this site). Where the docs give no figure, we say "no official figure". Nothing here was measured by us.
To size a home server, add up the official RAM and CPU requirements of every app you plan to run, then leave headroom for the OS and spikes. For example, Immich alone needs 6 GB of RAM (8 GB recommended). Tick your apps to see the documented RAM and cores, and which hardware class fits.
Tick the apps you plan to run and the calculator adds up the documented RAM and CPU figures, then points you to a hardware class. It is a starting point from documentation, not a benchmark.
Calculator
The live calculator needs JavaScript. It runs only in your browser and sends nothing. Without JavaScript, add up the figures in the table below by hand.
Official requirements per app
| App (version pinned on this site) | RAM (official) | CPU (official) | Source (checked 2026-10-25) |
|---|---|---|---|
| Immich v3.3.5 | Minimum 6 GB, recommended 8 GB ("For systems with only 4GB of RAM, Immich can be run with machine learning features disabled.") | Minimum 2 cores, recommended 4 cores | https://docs.immich.app/install/requirements |
| Jellyfin v12.3 | "at least 8GB is recommended for the average deployment. For a Linux server running without a GUI, 4GB may be enough." | No official core count (the docs recommend CPU models and GPUs for transcoding instead) | https://jellyfin.org/docs/general/administration/hardware-selection/ |
| Nextcloud 35 | "a minimum of 128MB RAM per process", recommended "a minimum of 512MB RAM per process" (per PHP process, not a total) | No official figure | https://docs.nextcloud.com/server/stable/admin_manual/installation/system_requirements.html |
| Vaultwarden 1.37.4 | No official figure | No official figure | https://github.com/dani-garcia/vaultwarden |
| Paperless-ngx v3.3.4 | No official figure (the FAQ says it runs on a Raspberry Pi; OCR is the slow part) | No official figure | https://github.com/paperless-ngx/paperless-ngx/blob/v3.3.4/docs/faq.md |
| Audiobookshelf v2.37.2 | No official figure | No official figure | https://www.audiobookshelf.org/docs |
| Home Assistant OS 18.3 (in a VM) | Minimum 2 GB | Minimum 2 vCPUs | https://www.home-assistant.io/installation/linux |
| Proxmox VE 9.2 host overhead | Recommended minimum 2 GB for the OS and Proxmox VE services, plus guest memory; with ZFS or Ceph about 1 GB more per TB of storage | 64-bit Intel or AMD CPU with Intel VT/AMD-V (no core count) | https://pve.proxmox.com/wiki/System_Requirements |
How to add it up
- RAM: add the documented figures for the apps you run. Apps with "no official figure" add nothing to the sum, so leave headroom for them. Nextcloud's figure is per process, so it is listed separately rather than added.
- CPU: the docs give core counts only for Immich and Home Assistant. Containers share cores, and no doc says how to combine them, so the calculator shows the largest single documented figure and the sum as a conservative upper bound.
- Proxmox: if you run apps in VMs on Proxmox, add the Proxmox host figure on top of each guest's memory.
Which hardware class?
These classes come from official spec sheets we already cover:
- Up to 16 GB of RAM in total: an Intel N100/N150-class mini PC can fit. Intel lists a 16 GB maximum, single channel for these chips. See Best mini PC for Jellyfin and Intel N100 vs i3-N305 vs ThinkCentre Tiny.
- More than 16 GB, or several VMs: look at a box with two memory slots. Lenovo PSREF lists up to 64 GB for the ThinkCentre M70q/M90q Gen 5 (see the same comparison). Install guide: Proxmox on a mini PC.
- Prefer the cloud? See the spec-matched VPS table.
- Immich in detail: Immich hardware requirements.
Running costs: estimate them with the power cost calculator.
Limits
- Minimums are what the software needs to start and run. Libraries, users, transcoding and machine learning push real use higher.
- The figures are from documentation, not our measurements.
Sources
- https://docs.immich.app/install/requirements
- https://jellyfin.org/docs/general/administration/hardware-selection/
- https://docs.nextcloud.com/server/stable/admin_manual/installation/system_requirements.html
- https://github.com/dani-garcia/vaultwarden
- https://github.com/paperless-ngx/paperless-ngx/blob/v3.3.4/docs/faq.md
- https://www.audiobookshelf.org/docs
- https://www.home-assistant.io/installation/linux
- https://pve.proxmox.com/wiki/System_Requirements
- https://www.intel.com/content/www/us/en/products/sku/241636/intel-processor-n150-6m-cache-up-to-3-60-ghz/specifications.html