Verdict

These are closely matched NAS drives of the same capacity - decide on price and warranty. Check the live $/TB above.

WD161KRYZ
WD Gold · 16TB · Enterprise
$850 ($53.13/TB)
WUH721816ALE6Lx
WD Ultrastar DC HC550 · 16TB · Enterprise
$694 ($43.40/TB)

Value at a glance

Price / TB
WD161KRYZ $53.13
WUH721816ALE6Lx $37.70
Capacity
WD161KRYZ 16 TB
WUH721816ALE6Lx 16 TB
Noise (idle)
WD161KRYZ 20 dB
WUH721816ALE6Lx 20 dB

Price history · US, cheapest per day

WD161KRYZ $850 WUH721816ALE6Lx $694
zoomed · drag to zoom
$900 $565 $230 Jul 2024 Dec 2024 May 2025 Sep 2025 Feb 2026 Jul 2026
WD161KRYZ WUH721816ALE6Lx
Capacity 16 TB 16 TB
Recording tech CMR CMR
RAID / NAS safe Yes Yes
Class Enterprise Enterprise
Spindle speed 7200 RPM 7200 RPM
Cache 512 MB 512 MB
Noise (idle) 20 dB 20 dB
Fill Helium Helium
Interface SATA SATA
Failure rate (AFR) - 0.88%
Price / TB $53.13 $37.70
Buy
$850
View at Amazon →
$694
View at Amazon →

Highlighted cells mark the stronger spec for a NAS build. Failure rates from Backblaze Drive Stats where available; $/TB uses the cheapest live price. Buy links are Amazon affiliate.

WD161KRYZ

No Backblaze failure data for this model.

5yr warranty · 550 TB/yr rated · 2,500,000h MTBF

WUH721816ALE6Lx

0.88% AFR vs 1.34% fleet avg

95% CI 0.78-0.98%

29,795 drives · ~36,808 drive-years · 323 failures · Backblaze thru Q1 2026

5yr warranty · 550 TB/yr rated · 2,500,000h MTBF