Backblaze, the online backup service I use, buys many spinning disk hard drives. And by a lot, I mean over 230,000 drives. They also keep data on which drives last and which fail. That’s pretty important when you are buying on their scale.

The good news for the rest of us is that they routinely share that data. Here’s the most recent data on their drives. A few things that stood out to me:

Drive Size Increases

4TB used to be the standard drive size. Now they are buying 16TB drives. These days you can put a lot of storage on a spinning disk.

Older Drives Still Fail

Even though manufacturers are better than ever at making reliable spinning disk drives, older ones still fail at an accelerating rate over time. If you use a spinning disk in your backup routine, you need to replace them occasionally. This is obvious, but seeing the data helps send that point home.

I had some four-year-old drives last year (the last two spinning drives in my fleet). I rotate the two drives locally and offsite as a last-line-of-defense backup. They hadn’t started failing, yet I knew they didn’t have much gas left in the tank, so I replaced them. The good news is that because spinning drives are getting so cheap, the cost to replace them is only going down, and spinning drives are just fine for these backup/archive-type jobs for most people.

Check out the Backblaze statistics if you’d like to get a better idea of who’s making the best spinning drives today.