The Seagate Exos X20z ST20000NM001J 20TB 7.2K RPM SATA 6Gb/s 3.5 (HOST MANAGED SMR) costs $0.0279/GB while the WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive costs $0.0327/GB. Seagate Exos X20z ST20000NM001J 20TB 7.2K RPM SATA 6Gb/s 3.5 (HOST MANAGED SMR) offers 15% better value per gigabyte as of August 2026. Both products are available on BuyPerUnit with prices from Amazon, Best Buy, and Newegg.
Seagate Exos X20z ST20000NM001J 20TB 7.2K RPM SATA 6Gb/s 3.5 (HOST MANAGED SMR) vs WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive — Which Is Better Value?
WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive
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Specification Comparison
| Spec | Seagate Exos X20z ST20000NM001J 20TB 7.2K RPM SATA 6Gb/s 3.5 (HOST MANAGED SMR) | WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive |
|---|---|---|
| Brand | Seagate | Western Digital |
| Capacity | 20TB | 18TB |
| $/GB | $0.0279 | $0.0327 |
| Price | $559.00 | $589.00 |
| Retailer | Newegg | Newegg |
| Category | Hard Drives (HDD) | Hard Drives (HDD) |
| Subcategory | hdd | hdd |
Price Across Retailers
Which Should You Buy?
Based on current pricing data, the Seagate Exos X20z ST20000NM001J 20TB 7.2K RPM SATA 6Gb/s 3.5 (HOST MANAGED SMR) offers better value at $0.0279//GB compared to the WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive at $0.0327//GB — that's roughly 15% less per gigabyte.
The best deal for the Seagate Exos X20z ST20000NM001J 20TB 7.2K RPM SATA 6Gb/s 3.5 (HOST MANAGED SMR) is $559.00 at Newegg, while the WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive starts at $589.00 at Newegg.
However, price per gigabyte isn't everything — consider factors like warranty, performance specs, brand reliability, and your specific capacity needs. Check each Seagate Exos X20z ST20000NM001J 20TB 7.2K RPM SATA 6Gb/s 3.5 (HOST MANAGED SMR) and WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive product page for detailed specifications and price history.
Frequently Asked Questions
Is Seagate Exos X20z ST20000NM001J 20TB 7.2K RPM SATA 6Gb/s 3.5 (HOST MANAGED SMR) or WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive a better deal?
As of August 2026, Seagate Exos X20z ST20000NM001J 20TB 7.2K RPM SATA 6Gb/s 3.5 (HOST MANAGED SMR) offers better value at $0.0279//GB compared to WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive at $0.0327//GB. That is approximately 15% better value per gigabyte.
What is the price per GB of Seagate Exos X20z ST20000NM001J 20TB 7.2K RPM SATA 6Gb/s 3.5 (HOST MANAGED SMR)?
The Seagate Exos X20z ST20000NM001J 20TB 7.2K RPM SATA 6Gb/s 3.5 (HOST MANAGED SMR) is currently priced at $0.0279/GB ($559.00 for 20TB) at Newegg.
Where can I buy WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive for the cheapest price?
The cheapest price for the WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive is $589.00 at Newegg, which works out to $0.0327/GB.