Dataset · 2022 to 2025 · computed from raw Backblaze files

Backblaze hard drive models added and retired, 2022 to 2025

Which hard-drive models Backblaze added or retired between January 1, 2022 and December 31, 2025, from the raw daily Drive Stats files (sixteen quarterly zips). Sample: all 66 model strings of drives of 3 TB or more, 388,670,883 drive days and 16,051 failures, with drives on December 31 of each year, exposure, failures and the 2022 to 2025 AFR with exact 95% Poisson intervals per model. Models added after 2022 Q1 held 79,349 of the 334,844 drives on December 31, 2025. One fleet, and model strings are used as they appear in the files.

File /data/datasets/backblaze-2022-2025-model-turnover.csv · JSON metadata · Chart (SVG) · Yearly AFR for long-lived models · All datasets

Population and method

Population: every model string of hard drives of 3 TB or more in Backblaze\u2019s own data centers in the daily Drive Stats files for January 1, 2022 to December 31, 2025 (sixteen quarterly zips, 1,461 daily files). That is 66 model strings, 388,670,883 drive days and 16,051 failures. The build checks that these two totals equal the totals of the by-manufacturer dataset, built from the same files.

A model is continuous if it has a drive day in 2022 Q1 and in 2025 Q4, added if it first appears later and is still there in 2025 Q4, retired if it is there in 2022 Q1 and gone by 2025 Q4, and added and retired if neither. Drives on December 31 are the rows of the model in the last daily file of each Q4. AFR is failures \u00f7 drive days \u00d7 365 \u00d7 100 over the whole window, with an exact two-sided 95% Poisson interval. Rows are ordered by drive days.

Chart

Counted here

• Of the 66 model strings, 33 are continuous, 15 added, 17 retired and 1 added and retired.
• Drives on December 31: 231,309, 270,267, 301,094, 334,844 for 2022 to 2025. Models added after 2022 Q1 held 79,349 (23.7%) of the 2025 total, and models retired by 2025 Q4 held 19,368 drives (8.4%) at the end of 2022.
• Pooled AFR over the window, with drive days: continuous 1.49% (345,700,206), added 0.81% (27,896,977), retired 3.27% (15,069,366).
• The largest retired model is ST4000DM000: 14,089,411 drive days, 1330 failures, 3.45% (3.26% to 3.64%), last seen in 2025 Q1.

Limits

• Association only, one fleet. Added, continuous and retired models differ in age, capacity and workload, and the pooled AFRs over a four-year window mix those years. This file does not say why Backblaze added or retired a model.
• Model strings are used as they appear. Some differ only in spacing or a prefix, such as "WDC WUH721414ALE6L4" with two spaces, and show up as separate rows that look retired. The file does not merge them, so the retired count includes renamed strings.
• Thin rows have intervals too wide to read, and a failure rate over a model\u2019s whole stay is not comparable with a one-year rate.
• Intervals assume failures are Poisson in drive days with a constant rate, which ignores clustering. They are probably too narrow.

Table

Columns

model (string)

Model string exactly as in the Backblaze daily files. Strings that differ only in spacing, such as "WDC WUH721414ALE6L4" with two spaces, are separate rows.

capacity_tb (integer)

Nominal capacity in terabytes, round(capacity_bytes / 1e12).

status (string)

continuous: seen in 2022 Q1 and in 2025 Q4. added: first seen after 2022 Q1 and still there in 2025 Q4. retired: seen in 2022 Q1 and not in 2025 Q4. added and retired: neither.

first_quarter (string)

First of the 16 quarters (2022 Q1 to 2025 Q4) in which the model has any drive day.

last_quarter (string)

Last of the 16 quarters in which the model has any drive day.

quarters_present (integer)

Number of the 16 quarters with any drive day.

drives_end_2022 (integer)

Rows of the model in the last daily file of Q4 2022, that is drives present on December 31, 2022.

drives_end_2023 (integer)

Same for December 31, 2023.

drives_end_2024 (integer)

Same for December 31, 2024.

drives_end_2025 (integer)

Same for December 31, 2025.

drive_days (integer)

Daily rows of the model from 2022-01-01 to 2025-12-31. This is the exposure.

failures (integer)

Rows with failure = 1 in the window.

afr_percent (number)

failures / drive_days * 365 * 100, two decimals, over the whole window. Computed here.

afr_low95 (number)

Lower bound of the exact two-sided 95% Poisson (Garwood) interval, in percent.

afr_high95 (number)

Upper bound of the same interval, in percent.

License

Derivative table computed from the Backblaze Drive Stats daily files for 2022 to 2025. Cite Backblaze if you use it. You are solely responsible for how you use it. Backblaze's dataset page allows sale of derivative works and forbids selling the Drive Stats data itself. This CSV is a 66-row aggregate, not the daily SMART archive, and that archive is not for sale.

Backblaze Drive Stats use terms · Hard Drive Test Data page

Sources

1. Backblaze Hard Drive Test Data, data_Q1_2022.zip (daily CSV files) (accessed 2026-10-11)
2. Backblaze Hard Drive Test Data, data_Q2_2022.zip (daily CSV files) (accessed 2026-10-11)
3. Backblaze Hard Drive Test Data, data_Q3_2022.zip (daily CSV files) (accessed 2026-10-11)
4. Backblaze Hard Drive Test Data, data_Q4_2022.zip (daily CSV files) (accessed 2026-10-11)
5. Backblaze Hard Drive Test Data, data_Q1_2023.zip (daily CSV files) (accessed 2026-10-11)
6. Backblaze Hard Drive Test Data, data_Q2_2023.zip (daily CSV files) (accessed 2026-10-11)
7. Backblaze Hard Drive Test Data, data_Q3_2023.zip (daily CSV files) (accessed 2026-10-11)
8. Backblaze Hard Drive Test Data, data_Q4_2023.zip (daily CSV files) (accessed 2026-10-11)
9. Backblaze Hard Drive Test Data, data_Q1_2024.zip (daily CSV files) (accessed 2026-10-11)
10. Backblaze Hard Drive Test Data, data_Q2_2024.zip (daily CSV files) (accessed 2026-10-11)
11. Backblaze Hard Drive Test Data, data_Q3_2024.zip (daily CSV files) (accessed 2026-10-11)
12. Backblaze Hard Drive Test Data, data_Q4_2024.zip (daily CSV files) (accessed 2026-10-11)
13. Backblaze Hard Drive Test Data, data_Q1_2025.zip (daily CSV files) (accessed 2026-10-11)
14. Backblaze Hard Drive Test Data, data_Q2_2025.zip (daily CSV files) (accessed 2026-10-11)
15. Backblaze Hard Drive Test Data, data_Q3_2025.zip (daily CSV files) (accessed 2026-10-11)
16. Backblaze Hard Drive Test Data, data_Q4_2025.zip (daily CSV files) (accessed 2026-10-11)
17. Backblaze Hard Drive Test Data page and use terms (accessed 2026-10-11)
18. Backblaze Drive Stats for 2025 (published annual table: 115,638,676 drive days, 4,317 failures, 1.36%) (accessed 2026-10-11)
19. Garwood, F. (1936). Fiducial limits for the Poisson distribution. Biometrika 28(3-4), 437-442 (accessed 2026-10-11)