Western Digital unveils massive 40TB HDD with energy-assisted recording tech — plans 100TB HAMR hard drives by 2029
HAMR HDDs to be accompanies by ePMR drives for several years.
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Western Digital on Tuesday announced plans to extend its energy-assisted perpendicular magnetic recording (ePMR) technology to 60TB, thus producing ePMR-based hard drives along with its heat-assisted magnetic recording (HAMR) for several years down the road to guarantee steady availability of high-capacity drives. The company intends to release its 40TB UltraSMR hard drive in the second half of this year, with its HAMR-based counterpart following in 2027. By 2029, Western Digital plans to offer 100TB HAMR-based HDDs.
Western Digital made several important announcements about its short-term, mid-term, and long-term hard disk drive roadmap at its Innovation Day 2026 event on Thursday. The key part of the announcement is that the company will extend usage of its ePMR technology to 60TB hard drives, which means that high-capacity ePMR HDDs will coexist with HAMR drives over the next several years. HAMR HDDs (of unknown capacity) remain on track for mass production in 2027 after getting qualified by Western Digital's hyperscale customers.
The flagship HDD from Western Digital this year will be its 40TB HDD based on the ePMR technology and using shingled track layout (SMR) with UltraSMR enhancements, which is currently being qualified by two hyperscale customers. Previously, the company planned to offer a 36TB HDD based on the ePMR 2 technology with conventional magnetic recording (CMR), a 40TB SMR drive, and a 44TB UltraSMR HDD.
This 40TB hard drive will not be the last ePMR-based product from the company, as Western Digital intends to keep using the technology for at least a couple of years before HAMR-powered solutions will take over when HDD capacities hit 60TB. Yet, these next-generation ePMR drives will be 'leveraging HAMR innovations without increasing power consumption.' While Western Digital yet has to disclose what it means, we assume that the company intends to use a unified platform for ePMR and HAMR drives with next-generation media that uses iron platinum (FePt), which allows to achieve much higher areal densities — think 2.5 Tb/inch2 – 3.5 Tb/inch2 — than is possible today.
"The result is unprecedented flexibility," a statement by Western Digital reads. "Hyperscalers and enterprises can adopt either technology on their own timelines with predictable capacity planning and seamless scaling – no forced technology transitions, no infrastructure disruptions, just continuous and accelerating capacity growth built on architecture they already trust."
For now, Western Digital does not disclose the capacity of its first HAMR drives, but it is safe to say that they will succeed its 40TB UltraSMR hard drive in 2027. Also, it looks like the company plans to advance its HAMR-based offerings at a high pace with plans to offer 100TB HAMD hard drives by 2029, essentially moving from 40TB in 2026 to 100TB in less than three years.
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Anton Shilov is a contributing writer at Tom’s Hardware. Over the past couple of decades, he has covered everything from CPUs and GPUs to supercomputers and from modern process technologies and latest fab tools to high-tech industry trends.