Western Digital Purple 12TB

Surveillance HDD

Part number WD121PURZ - 85GUCY0 · Purple series · 3.5" SATA HDD. If your machine is listed below, this drive is officially supported — not a forum workaround.

PurpleNAS HARD DRIVE3.5" SATA HDDWESTERN DIGITAL

Part of the Western Digital Purple series →

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48
Compatible NAS models
48 Syn · 0 QNAP · 0 Asus · 0 TM
By vendor
12 TB
Listed capacity
Western Digital
Manufacturer
Surveillance
Product line (manufacturer rating)
5400
Spindle speed (RPM)
CMR
Recording
256 MB
Cache
180 TB
Rated workload / year

Specifications are the manufacturer's published ratings for this product series; verify the exact part number before purchase.

Strong pick as a cold copy

Rated CMR (conventional magnetic recording) — the right recording type for a large cold copy. CMR keeps a full-library backup pass fast even at 16–24 TB, which is the whole point of the offline slot in a 3-2-1 plan: rotate two drives monthly, keep one powered off, and the backup tooling (Veeam, Duplicati, Hyper Backup, HBS 3) does the scheduling. Full rule and vendor tool table: 3-2-1 for NAS.

Compatibility verdict

It appears on the official compatibility lists of 48 machines and series — 48 Synology. This is a Surveillance-class drive: rated for heavier sustained workloads than desktop drives. It is a strong pick for a NAS running 24/7, large-array rebuilds or camera workloads, and enterprise lines are also the drives most widely listed across all five vendors' HCLs. Its series rating is on file as CMR (conventional) — what RAID rebuilds and full-library copies want.

Compatible NAS models

Synology DS1019+5-bay See its full HCL → Synology DS1141-bay See its full HCL → Synology DS115j1-bay See its full HCL → Synology DS1161-bay See its full HCL → Synology DS1181-bay See its full HCL → Synology DS119j1-bay See its full HCL → Synology DS120j1-bay See its full HCL → Synology DS15155-bay See its full HCL → Synology DS1515+5-bay See its full HCL → Synology DS15175-bay See its full HCL → Synology DS1517+5-bay See its full HCL → Synology DS1522+5-bay See its full HCL → Synology DS1618+6-bay See its full HCL → Synology DS1815+8-bay See its full HCL → Synology DS18178-bay See its full HCL → Synology DS1817+8-bay See its full HCL → Synology DS1819+8-bay See its full HCL → Synology DS213j2-bay See its full HCL → Synology DS214se2-bay See its full HCL → Synology DS215+2-bay See its full HCL → Synology DS2162-bay See its full HCL → Synology DS216+2-bay See its full HCL → Synology DS216+II2-bay See its full HCL → Synology DS216j2-bay See its full HCL → Synology DS216play2-bay See its full HCL → Synology DS216se2-bay See its full HCL → Synology DS2182-bay See its full HCL → Synology DS218+2-bay See its full HCL → Synology DS218j2-bay See its full HCL → Synology DS218play2-bay See its full HCL → Synology DS220j2-bay See its full HCL → Synology DS2232-bay See its full HCL → Synology DS4164-bay See its full HCL → Synology DS416play4-bay See its full HCL → Synology DS418j4-bay See its full HCL → Synology DS418play4-bay See its full HCL → Synology DS4234-bay See its full HCL → Synology DS7157-bay See its full HCL → Synology DS716+7-bay See its full HCL → Synology DS716+II7-bay See its full HCL → Synology DS718+7-bay See its full HCL → Synology DS723+7-bay See its full HCL → Synology DS916+4-bay See its full HCL → Synology DS918+4-bay See its full HCL → Synology DS923+4-bay See its full HCL → Synology DVA3219 See its full HCL → Synology RS820+ See its full HCL → Synology RS820RP+ See its full HCL →

Same-capacity alternatives

Other drives listed at 12 TB capacity, ranked by how many machines list them:

Western Digital WD121KRYZ 381 machines · Gold Toshiba MG07ACA12TE 329 machines · MG07ACA*** Seagate ST12000NM0008 315 machines · Exos X14 Seagate ST12000NE0007 311 machines · IronWolf Pro Seagate ST12000NE0008 296 machines · IronWolf Pro Seagate ST12000VE0008 287 machines · SkyHawkAI Western Digital HUH721212ALE600 287 machines · Ultrastar DC HC520 Western Digital HUH721212ALE604 285 machines · Ultrastar DC HC520

Quick answers

Is the WD121PURZ - 85GUCY0 officially compatible with my NAS?

It appears on the official compatibility lists of 48 machines and series — 48 Synology. Every machine page linked below shows the vendor's own list entry, refreshed daily.

Is the WD121PURZ - 85GUCY0 CMR or SMR?

As a Western Digital Purple drive, it is rated CMR. CMR (conventional magnetic recording) is what a RAID array wants: SMR drives slow rebuilds dramatically. See the <a href="/faq/cmr-vs-smr-nas-drives/">CMR vs SMR guide</a> for the full series table.

Is the WD121PURZ - 85GUCY0 a good NAS drive?

This is a Surveillance-class drive: rated for heavier sustained workloads than desktop drives. It is a strong pick for a NAS running 24/7, large-array rebuilds or camera workloads, and enterprise lines are also the drives most widely listed across all five vendors' HCLs. Its series rating is on file as CMR (conventional) — what RAID rebuilds and full-library copies want.

Can I use the WD121PURZ - 85GUCY0 for a 3-2-1 cold backup copy?

Rated CMR (conventional magnetic recording) — the right recording type for a large cold copy. CMR keeps a full-library backup pass fast even at 16–24 TB, which is the whole point of the offline slot in a 3-2-1 plan: rotate two drives monthly, keep one powered off, and the backup tooling (Veeam, Duplicati, Hyper Backup, HBS 3) does the scheduling. Full rule and vendor tool table: 3-2-1 for NAS.

What are alternatives to the WD121PURZ - 85GUCY0?

At the same capacity, the most widely listed alternatives are Western Digital WD121KRYZ (381 machines), Toshiba MG07ACA12TE (329 machines), Seagate ST12000NM0008 (315 machines). The full ranked list is below.