Cloud-based backup company Backblaze has published its full-year 2020 hard drive stats, revealing just how many hard drives in its data centers have failed over the past calendar year.

According to Backblaze’s data, the company added 39,792 hard drives to its collection 2020, bringing the total to 165,530 drives. Of those, 3,000 were boot drives, while the remaining 162,530 were data drives. Backblaze excluded 231 of its data drives from its data, as they ‘were either used for testing or [Backblaze] did not have at least 60 drives of the same model at any time during the year.’ This means the following data is based on a total of 162,299 hard drives.

As visible from the below graph, the Seagate 6TB drive (model: ST6000DX000) has the lowest annualized failure rate of just 0.23%, with HGST’s 4TB drive (model: HMS5C4040ALE640), 4TB drive (model: HMS5C4040BLE640), 8TB drive (model: HUH728080ALE600) and 12TB drive (model: HUH721212ALE600) not far behind with annualized failure rates of 0.27%, 0.27%, 0.29% and 0.31%, respectively.

Chart by Backblaze. Click to enlarge.

Backblaze says one of its goals going into 2020 was to diversify its hard drive lineup. This decision ‘proved to be prophetic in 2020, as the effects of Covid-19 began to creep into the world economy in March 2020.’ Specifically, Backblaze says its decision to diversify helped to ‘manage [its] supply chain through the manufacturing and shipping delays prevalent in the first several months of the pandemic.’

As a whole, Backblaze’s annualized failure rates for 2020 was 0.93%, which is less than half the 1.89% annualized failure rate it incurred in 2019. Backblaze says this reduction was a ‘group effort’ that ultimately saw all drives, new and old, small and large, perform well in 2020.

Backblaze further contextualizes its 2020 data with confidence intervals for each specific drive model and further dives into what specific drives it added to its lineup in 2020 in its blog post. You can even download the raw data from Backblaze as a ZIP file with CSV files for each chart towards the bottom of the post.

This data might not necessarily affect you if you aren’t a Backblaze user, but seeing drive failure rates from one of the largest cloud backup providers can help you better decide what drives might most be worth it for your personal storage solution, be it a single external hard drive or a dedicated RAID array.