GoKawiilSeagate, Toshiba, and Western Digital are the only remaining manufacturers of hard disk drives. They not only continue to produce these storage devices but are also actively advancing them as demand for HDDs rises again. While hard drives from these companies share many similarities, each relies on a different set of underlying technologies — distinct recording methods, actuator designs, platter materials, and magnetic alloys, among others — resulting in markedly different roadmaps. In this story, we examine these roadmaps and attempt to make sense of them.
The state of the HDD market
The amount of data that the world generates is higher than ever now that not only people, but also machines generate well over 400 million terabytes of data every single day, according to estimates made in 2024. Most of that data ends up in data centers, so Gartner predicts that data center storage capacity requirements will increase at a compound annual growth rate (CAGR) of 19.5% between 2024 and 2029 and will eventually reach 3.19 zettabytes (3.19 million PB, 3.19 billion TB). While a significant portion of that data will be stored on 3D NAND-based solid-state drives, the lion's share will reside on hard disk drives, as HDDs can still offer lower per-TB cost than even the cheapest NAND memory.
(Image credit: Toshiba)
Hard drives have been around for nearly 70 years, and over 220 companies have produced HDDs since they were introduced in 1956. In 2026, only three hard drive manufacturers — Seagate, Toshiba, and Western Digital — remain on the market, and their supply chains are largely integrated or consolidated, meaning that the industry has largely shrunk from where it used to be a decade ago. Nonetheless, the combination of per-TB cost, storage density, and storage performance that HDDs offer makes them competitive enough, particularly in AI and traditional data centers, which need to store plenty of data that must be accessed relatively quickly and therefore placed 'near online', or nearline.
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In fact, over 60% of hard drives shipped today are nearline HDDs, according to Nidec, the world's largest supplier of HDD motors. The remaining circa 40% are consumer and enterprise NAS hard drives, video surveillance HDDs, desktop HDDs (a declining category), external drives, laptop drives (an almost extinct category), and legacy high-performance enterprise HDDs (Toshiba only).
Nidec estimates that 119 million HDDs were shipped in its FY2023 (ending on March 31, 2024), and 125 million hard drives were shipped in its FY2024 (ending March 31, 2025), an indication that unit sales of mechanical storage devices are stable and are growing due to demand from AI and traditional data centers.
Unit sales of HDDs increased in calendar 2025 compared to calendar 2024, according to reports from Hoya (the only maker of glass substrates for HDD platters) and Resonac (the largest independent supplier of HDD platters), though exact numbers are unknown.
"While 2.5-inch substrates declined as forecasted, 3.5-inch substrates achieved double-digit growth, resulting in overall steady performance," said Eiichiro Ikeda, chief executive of Hoya. "Current demand is exceptionally strong and is expected to increase further. Preparations to enhance our supply capacity are also underway."
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