According to the report, best drives Backblaze currently use are the Hitachi Deskstar models (Deskstar 5K3000 and 7K3000, 3TB), which sport failure rates as low as 0.8 percent and as high as 2.9 percent annually.
The worst were the Seagate Barracuda 7200 models, 1.5TB drives that died at a rate of 25.4 percent annually.
The Seagate Desktop HDD.15, a 4TB drive racked up a 3.8 percent annual failure rate. But Seagate's drives failed that much more quickly than the competition, and the smaller-capacity drives failed more often.
Western Digital's drives did better, with the high end of its annual failure rates around 3.6 percent.
According to the stats Backblaze collected over the course of three years, the Hitachi drives were the most consistently reliable. Western Digital drives tended to have most of their failures up front, within the first couple of months of use. Seagate drives, died at a consistently higher rate, with a burst of deaths near the 20-month mark.