Every NAS-Rated CMR Drive, Best Value First

What counts as a NAS hard drive

A NAS hard drive is a mechanical drive built to run around the clock inside a multi-bay enclosure, with firmware tuned for vibration tolerance and RAID error recovery. The thing that matters most is the recording method: every drive we rank here uses CMR (conventional magnetic recording), which writes cleanly and rebuilds predictably. The trap to avoid is SMR (shingled recording), used in some old consumer drives like the WD Red EFAX, which overlaps tracks to gain density but rebuilds slowly under RAID and can be dropped from an array mid-rebuild.

The NAS-rated families differ mainly in workload rating and warranty rather than day-to-day speed. Seagate IronWolf is rated for 180TB a year with a 3 year warranty; IronWolf Pro carries a 5 year warranty and is rated 300TB a year on its NE-series model numbers and 550TB a year on its NT-series model numbers, in capacities to 32TB. WD Red Plus is rated for 180TB a year with 3 years and runs to 12TB, while WD Red Pro is rated for 550TB a year with 5 years and runs to 26TB. Toshiba N300 sits in the value lane at 180TB a year, 3 years, and capacities to 22TB.

Seagate Exos is the enterprise outlier. Seagate's data sheets give it a 2.5 million hour MTBF and a 5 year warranty, and it has the lowest price per terabyte once you reach the high capacities, at the cost of running louder and hotter than the home-focused drives. For a populated 4-bay sitting in a cupboard that is a fair trade; for a NAS on your desk it may not be.

How to choose a NAS drive

Buy at the sweet spot, then add bays

RAID is not a backup