Most reliable NAS hard drives
The most useful reliability signal is observed failures at scale, not a manufacturer MTBF number. We rank current NAS-suitable CMR drives by Backblaze's annualized failure rate (AFR), computed from hundreds of thousands of drive-days, with the fleet average shown for context on each drive page. Drives without large-scale field data sink to the bottom.
* Shown as a full table on desktop, and as cards on tablet and phone.
| Drive | Capacity | Tech | Class | Interface | AFR | €/TB | Price | |
|---|---|---|---|---|---|---|---|---|
| 1 |
ST16000NM000J Seagate Exos X18
|
16 TB | CMR | Enterprise | SATA | 0.17% | - | - |
| 2 |
MG11ACA24TE Toshiba MG11
|
24 TB | CMR | Enterprise | SATA | 0.42% | €43.71 | €1,049 |
| 3 |
WUH722222ALE6L4 WD Ultrastar DC HC570
|
22 TB | CMR | Enterprise | SATA | 0.45% | - | - |
| 4 |
ST16000NM001G Seagate Exos X16
|
16 TB | CMR | Enterprise | SATA | 0.53% | €43.06 | €689 |
| 5 |
WUH722626ALE6L4 WD Ultrastar DC HC590
|
26 TB | CMR | Enterprise | SATA | 0.67% | €53.11 | €1,381 |
| 6 |
MG10ACA20TE Toshiba MG10
|
20 TB | CMR | Enterprise | SATA | 0.68% | €45.75 | €915 |
| 7 |
WUH721414ALE6L4 WD Ultrastar DC HC530
|
14 TB | CMR | Enterprise | SATA | 0.72% | €54.39 | €761 |
| 8 |
WUH721816ALE6Lx WD Ultrastar DC HC550
|
16 TB | CMR | Enterprise | SATA | 0.88% | €51.62 | €826 |
| 9 |
ST12000NM001G Seagate Exos X16
|
12 TB | CMR | Enterprise | SATA | 0.97% | €71.27 | €855 |
| 10 |
MG07ACA14TE Toshiba MG07
|
14 TB | CMR | Enterprise | SATA | 1.16% | - | - |
Ranked by measured failure rate (Backblaze AFR). $/TB uses the cheapest live price where available.
How we rank reliability
We pin Backblaze Drive Stats to the exact models currently on sale, compute the annualized failure rate from failures over drive-days, and sort lowest first. The fleet-wide average appears on each drive page so a number has context: a 0.6% AFR means little without knowing whether it rests on one failure or fifty.
Reliability is one axis. Cross-check capacity, price per TB and noise before buying - a drive with a marginally lower AFR but a far worse price per TB is rarely the better array.
Frequently asked questions
- What is a good annualized failure rate?
- Below about 1% per year is solid for a hard drive at scale. A single low or zero figure from a small sample is not proof on its own - look at the drive count and age behind it too, which we show on each drive's page.
- Is Backblaze data representative of my home NAS?
- Partly. Backblaze runs enterprise drives 24/7 in a datacenter, so the AFR figures are strongest for Exos, Ultrastar and MG-class drives. Consumer NAS lines like IronWolf and WD Red Plus have little large-scale public failure data, so judge those on class, warranty and workload rating.
- Does a low failure rate mean I can skip backups?
- No. Every drive can fail, and AFR is a fleet average, not a guarantee for your unit. Keep a 3-2-1 backup - RAID gives you uptime, not a backup.