Most reliable hard drive models named: Backblaze 2025 report

American cloud storage provider Backblaze has released its annual hard drive reliability report covering 2025. Considered one of the most authoritative studies in the industry, the company operates hundreds of thousands of HDDs in real-world data center conditions and publishes open failure statistics. In 2025, its fleet included 344,196 drives with a combined runtime exceeding 115 million drive days—making the dataset exceptionally robust, as noted by Tom's Hardware.

Overall Trend: Failure Rates Continue to Decline

The average Annualized Failure Rate (AFR) in 2025 was 1.36%—the best result in the past three years. For comparison, AFR stood at 1.70% in 2023 and 1.57% in 2024. The continued decline suggests that drive reliability is improving, thanks to both better manufacturing quality and more effective drive selection and maintenance by Backblaze.

In the fourth quarter of 2025, AFR dropped even further to 1.13%, reinforcing the positive trend.

Reliability Leaders

The most stable models recorded virtually zero or minimal failures throughout the year. Among the standout performers:

• Seagate ST16000NM002J (16TB) — only one failure during the entire year.
• Western Digital WUH722626ALE6L4 (26TB) — likewise, just one failure.

These drives operate in large-scale storage arrays under continuous read/write workloads, making them strong candidates for NAS systems, servers, and enterprise storage deployments.

Backblaze also notes that high-capacity drives (16TB and above) are increasingly dominating its fleet and are demonstrating strong reliability overall.

Problematic Models and Causes

Not all drives performed equally well. The highest AFR was recorded for older 8TB HGST models (HUH728080ALE600), which reached 10.29%. The primary reason is age—these drives have been in operation for more than 7.5 years—combined with vibration stress in densely packed racks. They are now being phased out.

Another notable case involved 16TB Toshiba drives (MG08ACA16TEY and related models). In one quarter, their AFR spiked to 16.95%, but after a firmware update, it dropped to 4.14%. This serves as a clear example of how timely firmware updates can significantly improve reliability.

What This Means for Regular Users

The Backblaze report is not a direct buying guide for home PCs, since data center environments are far more demanding (24/7 operation, higher temperatures, constant vibration). However, it provides valuable real-world insight into long-term durability.

For users building a NAS or storage server, it makes sense to consider models that consistently maintain low AFR figures over multiple years, such as Seagate Exos, WD Gold/Ultrastar, and Toshiba’s MG series.

The overall takeaway is positive: hard drives are becoming more reliable, and the high-capacity segment (20–26TB) has matured significantly.

In Brief

Backblaze recorded a record-low average AFR of 1.36% in 2025—better than in 2023 and 2024. The most reliable models were Seagate ST16000NM002J (16TB) and Western Digital WUH722626ALE6L4 (26TB), each with just one failure during the year. Issues were observed with older 8TB HGST drives (10.29% AFR) and certain 16TB Toshiba models (up to 16.95% before firmware updates). The data is based on 344,000 drives and 115 million drive days—the largest publicly available HDD reliability dataset.