Seagate Exos vs WD Ultrastar
Exos and Ultrastar are the two dominant enterprise HDD families for datacenter, homelab, and high-capacity server storage. Both are rated for 24/7 operation, carry 5-year warranties at retail, and are designed for multi-drive chassis with vibration tolerance. In practice the choice often comes down to price at the capacity you need, firmware compatibility with your HBA or backplane, and whether you prefer Seagate or WD support.
Quick comparison
Exos (Seagate) and Ultrastar (WD/HGST legacy) both target the same workloads: always-on servers, JBODs, and storage arrays. Exos X-series tops out at 24 TB with helium-sealed models; Ultrastar HC-series reaches similar capacities. Both offer SAS and SATA interfaces. Workload ratings are typically 550 TB/year, with 2.5M-hour MTBF. For most buyers, the lowest price per TB at your target capacity is the right pick.
Prices updated hourly from Amazon US and UK. All links go directly to the retailer.
Seagate Exos — Current Prices
New Seagate Exos enterprise drives sorted by price per terabyte. Includes Exos X-series helium models across all available capacities.
Seagate Exos 7E10 8TB Internal Hard Drive HDD - 3.5 Inch 512e/4Kn SAS 6GB/s, 7.200 RPM, 256MB Cache and 2M MTBF for Enterprise, Data Centre (ST8000NM017B)
Seagate Exos 7E8 HDD 512E/4KN SAS
Seagate Exos X14 ST10000NM0478 - Hard drive - 10 TB - internal - 3.5" - SATA 6Gb/s - 7200 rpm - buffer: 256 MB
Seagate Exos 7E8, 8TB, Enterprise Internal Hard Drive, SAS, 3.5", for Business and Data Centre (ST8000NM001A)
Seagate Enterprise ST3000NM0025 3TB 7200RPM SAS 12.0 GB/s 128MB 512n Enterprise Hard Drive (3.5 inch, Exos 7E8 HDD 512N SAS)
Seagate Exos X24 ST20000NM007H - 20TB
Seagate Exos X24 24TB internal server Hard drive ST24000NM000C 3.5" HDD SATA3 512MB 7200RPM
Seagate Exos X18 12TB HDD 512E/4KN SAS
WD Ultrastar — Current Prices
New Western Digital Ultrastar enterprise drives sorted by price per terabyte. The Ultrastar HC-series carries on the HGST legacy of reliability.
Western Digital Ultrastar DC HC530 WUH721414ALE601 14TB 7.2K RPM SATA 6Gb/s 3.5in Hard Drive
HGST Ultrastar DC HC320 HUS728T8TAL5204 8 TB Hard Drive - 3.5 Internal - SAS [12Gb/s SAS]
Western Digital Ultrastar DC HC570 3.5" 22 TB Serial ATA III
Western Digital Ultrastar DC HC550 Enterprise Hard Drive 18TB (3.5" SATA 6Gbps, SAS 12Gbps, 7200RPM, 512MB Cache)
HGST Ultrastar He12 HUH721212ALE600 12 TB Hard Drive - 3.5" Internal - SATA (SATA/600) - 7200rpm
Western Digital WUH721414ALE6L4 14TB Ultrastar DC HC530 SATA HDD - 7200 RPM Class, SATA 6 Gb/s, 512MB Cache, 3.5"
Western Digital Ultrastar DC HC330 3.5" 10000 GB Serial ATA III
HGST Ultrastar He12 HUH721212AL4201 12 TB Hard Drive - SAS [12Gb/s SAS] - 3.5 Drive - Internal
High-Capacity Enterprise (14 TB+)
The largest enterprise drives from both families. More terabytes per slot means fewer bays, fewer HBAs, and lower power per usable TB.
Western Digital Ultrastar DC HC530 WUH721414ALE601 14TB 7.2K RPM SATA 6Gb/s 3.5in Hard Drive
Seagate Exos X14 ST10000NM0478 - Hard drive - 10 TB - internal - 3.5" - SATA 6Gb/s - 7200 rpm - buffer: 256 MB
Western Digital Ultrastar DC HC570 3.5" 22 TB Serial ATA III
Seagate Exos X24 ST20000NM007H - 20TB
Seagate Exos X24 24TB internal server Hard drive ST24000NM000C 3.5" HDD SATA3 512MB 7200RPM
Seagate Exos X18 Enterprise Class, 18TB, Enterprise Internal Hard Drive, SATA, 3,5" 6Gbit/s, 128MB cache ((ST18000NM000J)
Western Digital Ultrastar DC HC550 Enterprise Hard Drive 18TB (3.5" SATA 6Gbps, SAS 12Gbps, 7200RPM, 512MB Cache)
Western Digital WUH721414ALE6L4 14TB Ultrastar DC HC530 SATA HDD - 7200 RPM Class, SATA 6 Gb/s, 512MB Cache, 3.5"
Refurbished Exos & Ultrastar
Recertified datacenter pulls from both brands. Enterprise drives are designed for 2M+ hour MTBF, so a drive with 20-40K hours of use still has substantial life — ideal for homelabs and non-critical storage.
Why this matters: Refurbished enterprise drives often deliver the lowest price per TB available. Look for sellers that include SMART reports or a seller warranty. Drives with low reallocated sector counts and under 40,000 power-on hours are typically good candidates.
Seagate Exos 7E10 8TB Internal Hard Drive HDD - 3.5 Inch 512e/4Kn SAS 6GB/s, 7.200 RPM, 256MB Cache and 2M MTBF for Enterprise, Data Centre (ST8000NM017B)
Hgst 198944 Hard Drive 0f30146 3.5 Inch 12tb Es 72000rpm 256mb Sata 6gb/s 512e Se Ultrastar He12bare
Seagate Exos X16, 12TB, Enterprise Internal Hard Drive, SATA, 3.5", for Business and Data Centre (ST12000NM001G)
Western Digital HGST Ultrastar He10 HUH721008AL5204 8 TB Hard Drive - 3.5" Internal - SAS (12Gb/s SAS) - 7200rpm - 256 MB Buffer - 5 Year Warranty
Seagate EXOS X22 22TB Interne Server Festplatte ST22000NM000C 3,5 Zoll HDD SATA 6Gb/s 7200RPM SED 512E 512MB Cache (Renewed)
HGST, a Western Digital Company Ultrastar 7K6000 6000GB 7200RPM SAS 512E Ultra SE 128MB Cache 3.5-Inch Internal Bare or OEM Drives 0F22811
Seagate EXOS X24 24TB Interne Festplatte 3.5 Zoll SATA 3 Gbit/s 512 MB, ST24000NM000C (Renewed)
Seagate Exos X20 20TB Internal Hard Drive - 3.5 Inch Hyperscale SATA 6GB/s HDD, 7,200 RPM, 2.5M MTBF, 512e and 4Kn FastFormat, Low Latency with Enhanced Caching (ST20000NM007D)
Related Buying Guides
Best Enterprise Hard Drives
Compare enterprise HDD prices for Seagate Exos and WD Ultrastar. Datacenter-grade drives sorted by price per TB for servers and storage arrays.
Best Refurbished Hard Drives
Find the best refurbished and used hard drive deals sorted by price per TB. Enterprise pulls, recertified NAS drives, and high-capacity bargains from Amazon US and UK.
Best HDD Deals Right Now
Find the best hard drive deals sorted by price per terabyte. Compare new and refurbished HDDs across Amazon US and UK, updated hourly.