Home Assistant: hardware requirements guide
Smart home hub with integrations, dashboards and automations.
Hardware requirements by tier
Three tiers for every workload: the minimum that works, the recommended sweet spot, and the comfortable headroom level. These are the same tiers the WisePC decision engine uses when it plans a build around your goal.
| Tier | CPU cores | RAM | Storage | GPU | VRAM | Network |
|---|---|---|---|---|---|---|
| Minimum | 2 cores | 4 GB | 0.5 TB (ssd) | None | — | 1 GbE |
| Recommended | 4 cores | 8 GB | 1 TB (ssd) | None | — | 1 GbE |
| Comfortable | 8 cores | 16 GB | 2 TB (ssd) | any | — | 2.5 GbE |
| Overkill | 13 cores | 26 GB | 4 TB (ssd) | any | — | 2.5 GbE |
Beyond Comfortable — 13 cores, 26 GB RAM, 4 TB (SSD): headroom you will never use for this workload alone. Put the difference into storage, backup or silence.
Recommended system shape
Derived by the decision engine from the recommended tier — the same logic that plans full builds.
- Form factor
- sff
- Build style
- prebuilt
- Drive plan
- 2× 2TB NVMe
Light requirements (4 threads, 8GB RAM) fit a sff prebuilt system — simpler and more efficient than building from parts.
One box or a separate machine?
Whether this workload deserves its own system or should live on the main server.
Keep on the main server
Lightweight always-on service — a separate system would add cost, energy and maintenance for no benefit.
Storage arrays, priced
Five physical strategies for the recommended capacity — the same planner, drive model and reference prices as the storage planner tool.
| Strategy | Drives | Usable | Cost | Idle |
|---|---|---|---|---|
| Cheapest | 1× 4TB hdd | 4 TB · none | ≈ €100 | 5 W |
| Balanced | 1× 16TB hdd | 16 TB · none | ≈ €240 | 6 W |
| Redundant | 3× 8TB hdd | 8 TB · parity2 | ≈ €450 | 15 W |
| Expansion-friendly | 1× 20TB hdd | 20 TB · none | ≈ €300 | 7 W |
| PerformanceRecommended | 2× 4TB nvme | 4 TB · parity1 | ≈ €480 | 2 W |
For a fast working tier, go all-flash — the performance strategy protects speed without the HDD rebuild pain.
Backup is not storage
The extra copy that survives drive failure, deletion and ransomware — the same engine as the backup planner.
Protect 1TB with at least two copies on separate hardware, ideally one offsite. The recommended start is a dedicated NAS.
Recommended: External drive — One portable copy, unplugged when not backing up · ≈ €128
- No offsite copy (high): Add a second copy outside the building — cloud or a drive at a friend's house.
- No versioning (medium): Use a versioning-aware tool (restic, borg, Backblaze) that keeps history.
- Unscheduled backups (medium): Schedule backups automatically and monitor them.
- Backup on the same machine (medium): Keep the backup on separate hardware or offsite.
What will it cost?
Market-neutral EUR bands from the reference drive model (≈ = estimated street price). Live component prices resolve on the build page for your region.
- Storage array
- ≈ €100 – €480
- Array energy / year
- ≈ €37/yr (∼17 W idle)
Compute (CPU, board, RAM, GPU) is not included — see the recommended build for live prices.
Growth outlook
What happens when the data keeps growing — the same engine as the growth simulator.
This architecture becomes inadequate in year 2 — 2 bays needed. Plan the next step (bigger array, NAS or DAS, or a stronger platform) before then.
Exceeds max 2TB by 1TB — need larger array/DAS/NAS. Fresh Performance array for 3TB: 2 bays, ~480€.
Also covered in this guide
Automation
Scenes, schedules and automation engines (Node-RED etc.).
IoT
MQTT broker, device bridges, sensor integration.
Which tier do you need?
- Pick Minimum (2 cores, 4 GB RAM) only for a single-purpose machine on a tight budget — expect little headroom.
- Recommended (4 cores, 8 GB RAM) is the sweet spot: enough for the workload plus the usual side-services, without overspending.
- Pick Comfortable (8 cores, 16 GB RAM) when this workload shares the machine with others or will grow — you pay for headroom, not for anxiety.
- GPU rule for this workload: None.GPU rule for this workload: None (no discrete VRAM needed).
Frequently asked questions
How much RAM does home assistant need?
4 GB is the sensible minimum, 8 GB covers most real setups, and 16 GB gives comfortable headroom for growth and extra services.
How many CPU cores does home assistant need?
A 2-core CPU is the minimum, 4 cores is the recommended sweet spot, and 8 cores is comfortable when it shares the machine with other workloads.
Does home assistant need a dedicated GPU?
No — integrated graphics or a headless setup is enough.
What storage and network does home assistant expect?
Storage: 1 TB of SSD is the recommended baseline (0.5 TB minimum, 2 TB comfortable). Network: 1 GbE is the recommended baseline.
What runs well alongside home assistant?
It pairs naturally with: Automation, IoT, Object detection.
How much power does home assistant use?
The storage array idles around 17 W (≈ 37 €/year at 0.25 €/kWh). The full system adds CPU, board and fans on top — see the cost section for the honest bands.