Limits RegistryPUBLIC RECORD
Limits RegistrySeagate's Mozaic 3+ platform, which reached volume shipment in 2024-2025, uses heat-assisted magnetic recording (HAMR) to pack 3 TB of data onto each platter, enabling total drive capacities up to 36 TB (Exos M series) across 12 platters — the highest areal density in any shipping HDD product line as of its release. HAMR heats the disk surface with a laser during writing to allow smaller, more stable magnetic grains, extending the areal-density scaling that conventional perpendicular magnetic recording had begun to run out of headroom on.
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Seagate's Mozaic 3+ platform, which reached volume shipment in 2024-2025, uses heat-assisted magnetic recording (HAMR) to pack 3 TB of data onto each platter, enabling total drive capacities up to 36 TB (Exos M series) across 12 platters — the highest areal density in any shipping HDD product line as of its release. HAMR heats the disk surface with a laser during writing to allow smaller, more stable magnetic grains, extending the areal-density scaling that conventional perpendicular magnetic recording had begun to run out of headroom on.
The highest per-platter capacity achieved by a commercially shipping hard disk drive using heat-assisted magnetic recording (HAMR) technology, as of its general-availability announcement.
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Permanent ID limitsregistry.com/limits/LR-HAMR-HDD-AREAL-DENSITY
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Limits Registry. LR-HAMR-HDD-AREAL-DENSITY. Highest areal density in a shipping hard disk drive. 2026.