Do I need CMR drives for Plex?

Yes. CMR (conventional magnetic recording) handles sustained writes and RAID rebuilds reliably. SMR drives can slow to a crawl or drop out of an array under heavy write load, so avoid them for any multi-drive Plex setup.

How much capacity do I need for Plex?

Plan for roughly 5-15GB per HD movie and 25-50GB per 4K movie. Most enthusiasts start at 8-16TB per drive and add more over time. Buying larger drives now usually costs less per terabyte than upgrading later.

Should I use enterprise drives for Plex?

Enterprise drives like the Seagate Exos or WD Ultrastar are faster and carry longer warranties, but they are louder and use more power. For a home Plex box, NAS-class drives are usually the better balance; choose enterprise for maximum capacity and endurance.

Best NAS hard drives for Plex

A Plex server lives or dies on two things: enough room for the library, and drives that keep spinning for years. That means high-capacity CMR drives rated for NAS or enterprise duty - never SMR, which chokes on the sustained writes a growing library and a RAID rebuild throw at it.

The list below is every CMR drive in our catalog of 8TB or larger, ranked by measured annualized failure rate (AFR) from Backblaze where we have it.

	Drive	Capacity	Tech	Class	Interface	AFR	€/TB	Price
1	ST16000NM000J Seagate Exos X18	16 TB	CMR	Enterprise	SATA	0.22%	€27.49	€440
2	WUH722626ALE6L4 WD Ultrastar DC HC590	26 TB	CMR	Enterprise	SATA	0.40%	€41.42	€1,077
3	WUH722222ALE6L4 WD Ultrastar DC HC570	22 TB	CMR	Enterprise	SATA	0.47%	€51.11	€1,124
4	ST16000NM001G Seagate Exos X16	16 TB	CMR	Enterprise	SATA	0.54%	€31.16	€499
5	MG10ACA20TE Toshiba MG10	20 TB	CMR	Enterprise	SATA	0.59%	€43.30	€866
6	MG11ACA24TE Toshiba MG11	24 TB	CMR	Enterprise	SATA	0.68%	€42.38	€1,017
7	WUH721816ALE6Lx WD Ultrastar DC HC550	16 TB	CMR	Enterprise	SATA	0.80%	€41.25	€660
8	WUH721414ALE6L4 WD Ultrastar DC HC530	14 TB	CMR	Enterprise	SATA	0.81%	-	-
9	ST12000NM001G Seagate Exos X16	12 TB	CMR	Enterprise	SATA	0.96%	€36.77	€441
10	MG07ACA14TE Toshiba MG07	14 TB	CMR	Enterprise	SATA	1.18%	-	-

Ranked by measured failure rate (Backblaze AFR). $/TB shows once live prices are wired.

What matters in a Plex drive

A Plex library is almost all large sequential reads and writes, which is exactly what big spinning disks are good at. You don't need flash for media storage - you need capacity, reliability, and CMR recording. The transcoding load lands on your CPU or GPU, not the drives.

Capacity

Buy bigger than feels sensible. Libraries only grow, and per-terabyte cost drops as capacity rises, so one 16TB drive usually beats two 8TB drives on price and leaves bays free for later. A rough yardstick: 25-50GB per 4K film, so a 16TB drive holds a few hundred of them.

CMR, not SMR

SMR drives overlap tracks to pack in capacity, then pay for it with slow read-modify-write cycles on every rewrite. In an array that shows up as timeouts and dropped drives mid-rebuild. Every drive on this list is CMR.

Reliability

Where Backblaze publishes failure data, we rank by it - a lower AFR means fewer 3am "drive failed" emails. The big enterprise drives that suit a large Plex box (Exos, Ultrastar) post some of the lowest rates around, often 0.5-0.7%. Consumer NAS models frequently have no large-scale data, which is normal; lean on the warranty and workload rating there.

Our picks

The table above ranks itself from our catalog and updates as the data does. Click any model for full specs, its AFR, and a CMR/SMR confirmation before you buy.

Frequently asked questions

Do I need CMR drives for Plex?: Yes. CMR (conventional magnetic recording) handles sustained writes and RAID rebuilds reliably. SMR drives can slow to a crawl or drop out of an array under heavy write load, so avoid them for any multi-drive Plex setup.
How much capacity do I need for Plex?: Plan for roughly 5-15GB per HD movie and 25-50GB per 4K movie. Most enthusiasts start at 8-16TB per drive and add more over time. Buying larger drives now usually costs less per terabyte than upgrading later.
Should I use enterprise drives for Plex?: Enterprise drives like the Seagate Exos or WD Ultrastar are faster and carry longer warranties, but they are louder and use more power. For a home Plex box, NAS-class drives are usually the better balance; choose enterprise for maximum capacity and endurance.