Backblaze's Q2 2026 Drive Stats report covers 354,415 hard drives monitored from April through June, producing an annualized failure rate of 1.73% — the highest quarterly figure the company has reported in some time. Lifetime AFR ticked up slightly to 1.41%. The dataset remains the largest public corpus of real-world hard drive reliability data, now spanning more than 13 years of continuous publication. The quarterly numbers are skewed upward by three outliers above the 6.95% threshold: an aging 12TB HGST at 7.63%, a low-count 10TB Seagate at 9.33%, and a low-count 14TB Seagate at 8.26%. Age is the dominant factor — the HGST drives are nearly seven years old, the 10TB Seagate roughly 8.5 years — while the two Seagate models carry small populations that amplify individual failures into high AFRs. More concerning: 10 of 31 drive models exceeded 3.0% AFR, a distribution Backblaze notes is skewed higher than usual even beyond the outliers. Seagate swept the zero-failure honor roll with three models (8TB, 12TB, and 14TB) and a fourth model at just one failure. The top performers by lifetime AFR are dominated by newer, higher-capacity WDC and Toshiba drives: the WDC 14TB WUH721414ALE6L4 at 0.54%, the WDC 16TB WUH721816ALE6L4 at 0.56%, the WDC 22TB at 0.58%, and the Toshiba 24TB MG11ACA24TE at 0.50%. Capacity and youth correlate strongly with reliability in the fleet. For the second consecutive quarter, no new drive models entered the fleet — an unusual drought. But deployment is concentrating sharply at the 20TB-and-above tier, which now exceeds 25% of the total dataset. The 24TB Seagate ST24000NM002H added roughly 9,631 drives at an average age of just 12.2 months, posting a 3.3% quarterly AFR that bears watching as the population matures. Toshiba's 20TB MG10ACA20TE (25,270 drives, 1.1% quarterly AFR) and 24TB MG11ACA24TE (9,620 drives, 0.58% quarterly AFR) look strong early. The report's most forward-looking section addresses the CMR-to-SMR transition. Conventional magnetic recording (CMR) writes non-overlapping tracks with guard space; shingled magnetic recording (SMR) overlaps tracks like roof shingles, exploiting the size differential between read and write heads. SMR enables higher areal density — Western Digital has announced a 40TB UltraSMR drive with a roadmap to 100TB by 2029 — but introduces write amplification: rewriting a single track requires rewriting adjacent overlapping tracks. For sequential workloads this is invisible; for random writes it is a fundamental architectural penalty. Two retired models exited the fleet this quarter: the 4TB HGST HMS5C4040BLE640 at nearly nine years of service and the 8TB HGST HUH728080ALE600 at nearly eight. The gradual replacement of these legacy drives with 20TB+ models is shifting the fleet's center of gravity, and the reliability characteristics of SMR drives at scale remain unproven in this dataset. Backblaze continues to publish the raw data for download, making this one of the few genuinely open datasets in enterprise storage. The transparency is the product: 13 years of quarterly reports with consistent methodology, no paywalls, and no vendor lock-in on the analysis. The question is whether the transition to SMR and ultra-high-capacity drives will maintain the reliability baseline that CMR established, or whether the write-amplification tradeoff introduces new failure modes the industry hasn't yet characterized at fleet scale.
