Backblaze Study: HGST and Western Digital Drive Failure Rates Below Seagate; 1°C Rise Adds 2.1%

A study based on Backblaze storage drive data shows that HGST and Western Digital hard drives have lower failure rates than Seagate and Toshiba. The study analyzed 443,156 drives used between 2013 and the second quarter of 2025, covering more than 1.66 million drive-years of usage. The research team adjusted the model to eliminate the impact of differing drive-age distributions across batches. Under comparable conditions, HGST drives had a failure rate equal to 41% of Seagate's, Western Digital 52%, and Toshiba 107%. HGST ranked first in reliability, but that brand has been acquired by Western Digital and is being phased out. The data show that HGST accounted for a large share of new drives installed in 2014, Seagate dominated from 2015 to 2020, Toshiba's new-installation peak came in 2023, and Western Digital led in 2024. The research adjusted its analytical model to exclude the bias of drives being retired before failure. As drives age, Toshiba's failure behavior changes most markedly, with the monthly failure rate surging more than fourfold after 60 months of service, while other brands generally remained lower over the same period. These conclusions apply to data-center environments, not consumer-grade PCs. Backblaze's annual report shows an overall annualized drive failure rate of 1.36% in 2025. Each 1°C rise in drive temperature is associated with a 2.1% increase in the failure rate.