Dataset · Q2 2026 · vendor claim
Backblaze Q2 2026 hard drive AFR by model
Backblaze's published Q2 2026 quarterly hard-drive annualized failure rate was 1.73% (vendor claim): 1,498 failures across 31,553,350 drive days on 354,415 drives. This download is the 31-model table for April 1 through June 30, 2026 inclusive (drive count above 100 and drive days above 10,000), not the daily SMART archive.
Download CSV31 rows · 8 columns · CSVMethod
The CSV transcribes the model table in Backblaze’s Q2 2026 Drive Stats report, published September 29, 2026. Backblaze included models with a drive count above 100 and drive days above 10,000 as of June 30, 2026. The reporting period is April 1 through June 30, 2026 inclusive. Each AFR cell is copied as printed. Counted here, every copied AFR matches failures ÷ drive days × 365 × 100 within 0.01 percentage point, and the 31 rows sum to the report’s totals row.
Vendor claim: Backblaze monitored 359,101 drives used to store data, then removed 3,881 boot drives and 705 hard drives that missed the inclusion criteria, leaving 354,415 hard drives. The paragraph above the table calls those rates “for Q1 2026.” The table title is “Backblaze Hard Drive Failure Rates for Q2 2026,” the dates are the second quarter, and the totals match the Q2 2026 snapshot on the Drive Stats dataset page. This file follows the table.
The report’s lifetime table is a different population: 27 models, 353,041 drives, 558,148,607 drive days, 21,609 failures, and 1.41% AFR (vendor claim). The dataset page’s lifetime line matches those drive days, failures, and the 1.41% AFR. It does not list 354,415 as the lifetime drive count. Vendor claim: four models in this quarterly file miss the lifetime rule (more than 500 drives and more than 100,000 drive days) and are absent there: ST8000NM000A, ST14000NM000J, ST16000NM000J, and ST16000NM002J.
This site does not host the daily SMART archive. Vendor claim: Backblaze lists the Q2 2026 zip twice as a 2.1 GB zip, 11.7 GB on disk, and 91 files, one CSV per day named YYYY-MM-DD.csv. Canonical file: data_Q2_2026.zip. The dataset page warns that the SMART schema changes from quarter to quarter.
Limits
- One operator’s data-center fleet, not an industry sample. Rates in the summary and the model table are vendor claims.
- Counted here, 359,101 − 3,881 − 705 = 354,515, which is 100 drives above the 354,415 cohort the rows actually sum to. The dataset-page snapshot also uses 354,415. This file does not decide which stated count is wrong.
- Do not use 354,415 as the lifetime drive count. The lifetime total on the same report is 353,041 drives at 1.41% AFR.
- The report says seven models still had an AFR above 3.0%, and also that 10 of 31 did. Those sentences disagree. Use the AFR column. The count from this file is under Counted here.
- Vendor claim, September 29, 2026 press release: the quarterly AFR rose from 1.24% in Q1 2026, and three models exceeded a 6.95% outlier threshold. The 1.24% figure is not recomputed here and is not a column.
- Vendor claim: the 9.33% and 8.26% Seagate models had small populations (965 and 1,235 drives), and the 7.63% HGST model was nearly seven years old while the 10 TB Seagate was nearly 8.5 years old. Published ages in this file for those two are 83.8 and 101.7 months.
- Vendor claim: two retired models are not rows here, the 4 TB HGST HMS5C4040BLE640 and the 8 TB HGST HUH728080ALE600. The report also says no new drive model entered the fleet, and that none of the tabulated drives are SMR.
- The source table publishes no confidence interval. Average age is not an input to AFR. Selling Backblaze’s Drive Stats data itself is not allowed.
Counted here
From this CSV, not from the report’s prose: 354,415 drives, 31,553,350 drive days, 1,498 failures. Recomputed cohort AFR is 1.7328%, which rounds to the published 1.73%.
- HGST: 25,489 drives (7.19%), 296 failures.
- Seagate: 112,567 drives (31.76%), 573 failures.
- Toshiba: 125,050 drives (35.28%), 424 failures.
- WDC: 91,309 drives (25.76%), 205 failures.
Vendor claim, dataset page: population shares HGST 7.2, Seagate 31.76, Toshiba 35.28, and WDC 25.76. The shares above are drive count divided by the quarterly cohort, before that page rounds HGST to 7.2.
Drives of 20 TB and larger: 97,398 (27.48%) across 5 models. Vendor claim: the report calls that group more than 25% of the quarter’s dataset.
- Seagate ST24000NM002H (24 TB, 9,631 drives, AFR 3.3%)
- Toshiba MG10ACA20TE (20 TB, 25,270 drives, AFR 1.1%)
- Toshiba MG11ACA24TE (24 TB, 9,620 drives, AFR 0.58%)
- WDC WUH722222ALE6L4 (22 TB, 45,665 drives, AFR 0.55%)
- WDC WUH722626ALE6L4 (26 TB, 7,212 drives, AFR 0.95%)
Published AFR strictly above 3.0%: 11 of 31 models.
- HGST HUH721212ALE604 (12 TB, 13,196 drives, AFR 3.34%)
- HGST HUH721212ALN604 (12 TB, 9,694 drives, AFR 7.63%)
- Seagate ST8000NM0055 (8 TB, 13,112 drives, AFR 3.44%)
- Seagate ST10000NM0086 (10 TB, 965 drives, AFR 9.33%)
- Seagate ST12000NM0007 (12 TB, 972 drives, AFR 4.17%)
- Seagate ST12000NM0008 (12 TB, 18,521 drives, AFR 3.17%)
- Seagate ST14000NM0138 (14 TB, 1,235 drives, AFR 8.26%)
- Seagate ST16000NM002J (16 TB, 467 drives, AFR 3.47%)
- Seagate ST24000NM002H (24 TB, 9,631 drives, AFR 3.3%)
- Toshiba MG08ACA16TEY (16 TB, 4,857 drives, AFR 3.66%)
- WDC WUH721816ALE6L0 (16 TB, 2,970 drives, AFR 4.07%)
Published AFR above the 6.95% outlier threshold stated in the press release: 3 models.
- HGST HUH721212ALN604 (12 TB, 9,694 drives, AFR 7.63%)
- Seagate ST10000NM0086 (10 TB, 965 drives, AFR 9.33%)
- Seagate ST14000NM0138 (14 TB, 1,235 drives, AFR 8.26%)
Zero failures this quarter: 3 models.
- Seagate ST8000NM000A (8 TB, 239 drives, AFR 0%)
- Seagate ST12000NM000J (12 TB, 1,079 drives, AFR 0%)
- Seagate ST14000NM000J (14 TB, 497 drives, AFR 0%)
Model table
| MFG | Model | Size (TB) | Drive count | Avg. age (months) | Drive days | Failures | AFR (%) |
|---|---|---|---|---|---|---|---|
| HGST | HUH721212ALE600 | 12 | 2,599 | 78.4 | 236,107 | 7 | 1.08 |
| HGST | HUH721212ALE604 | 12 | 13,196 | 59.4 | 1,190,182 | 109 | 3.34 |
| HGST | HUH721212ALN604 | 12 | 9,694 | 83.8 | 861,297 | 180 | 7.63 |
| Seagate | ST8000DM002 | 8 | 6,903 | 114.8 | 563,210 | 38 | 2.46 |
| Seagate | ST8000NM000A | 8 | 239 | 40.4 | 21,499 | 0 | 0 |
| Seagate | ST8000NM0055 | 8 | 13,112 | 104.7 | 1,177,541 | 111 | 3.44 |
| Seagate | ST10000NM0086 | 10 | 965 | 101.7 | 86,092 | 22 | 9.33 |
| Seagate | ST12000NM0007 | 12 | 972 | 78.8 | 87,496 | 10 | 4.17 |
| Seagate | ST12000NM0008 | 12 | 18,521 | 73.7 | 1,671,057 | 145 | 3.17 |
| Seagate | ST12000NM000J | 12 | 1,079 | 22 | 97,746 | 0 | 0 |
| Seagate | ST12000NM001G | 12 | 13,177 | 63.7 | 1,193,856 | 44 | 1.35 |
| Seagate | ST14000NM000J | 14 | 497 | 17 | 43,349 | 0 | 0 |
| Seagate | ST14000NM001G | 14 | 10,498 | 63.2 | 949,396 | 39 | 1.5 |
| Seagate | ST14000NM0138 | 14 | 1,235 | 65.5 | 110,410 | 25 | 8.26 |
| Seagate | ST16000NM000J | 16 | 171 | 15.4 | 14,221 | 1 | 2.57 |
| Seagate | ST16000NM001G | 16 | 35,100 | 43.7 | 3,162,117 | 56 | 0.65 |
| Seagate | ST16000NM002J | 16 | 467 | 41.7 | 42,086 | 4 | 3.47 |
| Seagate | ST24000NM002H | 24 | 9,631 | 12.2 | 861,587 | 78 | 3.3 |
| Toshiba | MG07ACA14TA | 14 | 37,171 | 67.1 | 3,368,924 | 179 | 1.94 |
| Toshiba | MG07ACA14TEY | 14 | 989 | 42.8 | 89,164 | 6 | 2.46 |
| Toshiba | MG08ACA16TA | 16 | 39,932 | 33.7 | 3,614,263 | 100 | 1.01 |
| Toshiba | MG08ACA16TE | 16 | 6,306 | 51.4 | 568,379 | 16 | 1.03 |
| Toshiba | MG08ACA16TEY | 16 | 4,857 | 53.5 | 439,243 | 44 | 3.66 |
| Toshiba | MG09ACA16TE | 16 | 905 | 6.2 | 68,429 | 2 | 1.07 |
| Toshiba | MG10ACA20TE | 20 | 25,270 | 12.1 | 2,117,524 | 64 | 1.1 |
| Toshiba | MG11ACA24TE | 24 | 9,620 | 5.8 | 824,903 | 13 | 0.58 |
| WDC | WUH721414ALE6L4 | 14 | 8,635 | 64.2 | 783,318 | 23 | 1.07 |
| WDC | WUH721816ALE6L0 | 16 | 2,970 | 53.3 | 268,875 | 30 | 4.07 |
| WDC | WUH721816ALE6L4 | 16 | 26,827 | 37.5 | 2,432,374 | 77 | 1.16 |
| WDC | WUH722222ALE6L4 | 22 | 45,665 | 19.1 | 4,146,339 | 63 | 0.55 |
| WDC | WUH722626ALE6L4 | 26 | 7,212 | 3.4 | 462,366 | 12 | 0.95 |
Cohort totals
| Cohort | Drives | Drive days | Failures | AFR | Where stated |
|---|---|---|---|---|---|
| Q2 2026 quarterly | 354,415 | 31,553,350 | 1,498 | 1.73% | Report totals row and the dataset-page Q2 snapshot. This CSV’s rows sum to the same drives, days, and failures. |
| Lifetime through June 30, 2026 | 353,041 | 558,148,607 | 21,609 | 1.41% | Report lifetime totals. The dataset page matches the days, failures, and 1.41%, and does not use 354,415 as this drive count. |
| Calendar 2025 | not stated | 115,638,676 | 4,317 | 1.36% | Dataset-page snapshot only. That row did not give a drive count. |
Columns
- mfg
- Manufacturer label as published by Backblaze: HGST, Seagate, Toshiba, or WDC.
- model
- Drive model identifier as published.
- size_tb
- Nominal capacity in terabytes as published.
- drive_count
- Drives of this model in the quarterly cohort.
- avg_age_months
- Average age in months as published. Not an input to the AFR column.
- drive_days
- Drive-days observed for this model in the quarter.
- failures
- Drives that failed in the quarter, as published.
- afr_percent
- Annualized failure rate in percent, copied as published rather than refit.
License
Derivative table transcribed from Backblaze Drive Stats for Q2 2026. 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. The Q2 2026 report restates citation, sole responsibility, and the ban on selling the data, and does not restate the derivative-works permission. This CSV is not Backblaze's daily SMART archive, and that archive is not for sale.
Backblaze Drive Stats use terms · Q2 2026 report · Canonical daily archive (2.1 GB zip, not mirrored here)