Annual failure rate drops to 1.36% across 344,000+ drives; high-capacity models on the rise as first 26TB drives enter service
SAN MATEO, Calif. – Backblaze, Inc. (Nasdaq: BLZE), the high-performance cloud storage platform for the AI era, today published its 2025 Year-End Drive Stats report. The report analyzes the performance of 344,196 hard drives across 30 models.
The 2025 yearly annualized failure rate (AFR) was 1.36%, down from 1.55% in 2024. Q4 2025 posted an even stronger quarterly AFR of 1.13%. Lifetime AFR held steady at 1.30%, a figure that has remained consistent quarter over quarter, reflecting both drive quality and active fleet management practices.
The fleet’s composition continued to shift toward higher-capacity storage. Drives in the 14–16TB range now account for 52% of active drives, while 20TB+ models account for nearly 23%. Backblaze deployed its first 26TB drive this quarter, the WDC WUH722626ALE6L4, which recorded one failure in its initial period of service. This shift toward high-capacity models has been driven by three key trends across the hard drive industry: cost per gigabyte has declined steadily over the years, storage capacities continue to grow, but the availability of smaller drives for enterprises has declined.
Backblaze has also highlighted the highest-performing drive models within the storage fleet for the last quarter:
- HGST HMS5C4040BLE640 4TB: 1 failure out of 187 drives
- Seagate ST8000NM000A 8TB: 0 failures out of 247 drives
- Seagate ST12000NM000J 12TB: 1 failure out of 1,066 drives
- Seagate ST16000NM000J 16TB: 1 failure out of 112 drives
- Seagate ST16000NM002J 16TB: 0 failures out of 465 drives
- WDC WUH722626ALE6L4 26TB: 1 failure out of 1,201 drives
“For 13 years, Drive Stats has given us and the broader storage community a clear view of how drives perform at scale,” said Pat Patterson, Chief Technical Evangelist at Backblaze. “Today, as we increase density across our global data centers with higher-capacity drives, that operational knowledge is central to our strategy for serving AI and neocloud workloads.”
The full 2025 Drive Stats report and downloadable dataset are available at www.backblaze.com/drivestats/. Backblaze will also host a webinar to walk through the 2025 annualized failure rates, break down the data for interesting trends, and share the latest from the Backblaze drive fleet happenings on Wednesday, February 18, 2026 at 10:00 a.m. PT.
FAQs
What does the lifetime AFR tell us about fleet health?
The lifetime AFR has held near 1.30% for several consecutive quarters. This consistency reflects both drive model quality and proactive drive qualification processes and fleet maintenance: Backblaze tests drives before they enter the fleet; then monitors and replaces drives based on risk factors before they fail.
Why is the fleet shifting toward higher-capacity drives?
The cost per gigabyte has dropped, while smaller-capacity enterprise drives have become harder to source. Additionally, higher capacity drives allow data centers to increase storage density, maximizing the amount of storage available per server rack. Backblaze deploys new drives in full vault rollouts of 1,200 drives at a time.
Is the Drive Stats dataset publicly available?
Yes. Backblaze publishes the complete dataset for free at www.backblaze.com/drivestats/. The Drive Stats dataset represents the industry’s largest publicly accessible record of hard drive reliability.
About Backblaze
Backblaze (NASDAQ: BLZE) gives businesses the freedom to innovate without limits by removing the barriers of lock-in, complexity, and cost. Our high-performance cloud object storage accelerates AI workflows, powers data-heavy applications, streamlines media management, and protects critical data. As an award-winning independent cloud, we provide unparalleled levels of interoperability that enables over 500,000 of our customers to reach and serve hundreds of millions of end users in 175 countries around the world. For more information, please go to www.backblaze.com.
