The Seagate Exos X20 ST18000NM003D 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5' Internal Hard Drive (ST18000NM003D) costs $0.0353/GB while the WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive costs $0.0327/GB. WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive offers 7% better value per gigabyte as of August 2026. Both products are available on BuyPerUnit with prices from Amazon, Best Buy, and Newegg.
Seagate Exos X20 ST18000NM003D 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5' Internal Hard Drive (ST18000NM003D) 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 X20 ST18000NM003D 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5' Internal Hard Drive (ST18000NM003D) | WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive |
|---|---|---|
| Brand | Seagate | Western Digital |
| Capacity | 18TB | 18TB |
| $/GB | $0.0353 | $0.0327 |
| Price | $635.00 | $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 WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive offers better value at $0.0327//GB compared to the Seagate Exos X20 ST18000NM003D 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5' Internal Hard Drive (ST18000NM003D) at $0.0353//GB — that's roughly 7% less per gigabyte.
The best deal for the WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive is $589.00 at Newegg, while the Seagate Exos X20 ST18000NM003D 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5' Internal Hard Drive (ST18000NM003D) starts at $635.00 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 X20 ST18000NM003D 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5' Internal Hard Drive (ST18000NM003D) 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 X20 ST18000NM003D 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5' Internal Hard Drive (ST18000NM003D) or WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive a better deal?
As of August 2026, WD Purple WD180PURZ 18TB 7200 RPM 512MB Cache SATA 6.0Gb/s 3.5' Hard Drive offers better value at $0.0327//GB compared to Seagate Exos X20 ST18000NM003D 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5' Internal Hard Drive (ST18000NM003D) at $0.0353//GB. That is approximately 7% better value per gigabyte.
What is the price per GB of Seagate Exos X20 ST18000NM003D 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5' Internal Hard Drive (ST18000NM003D)?
The Seagate Exos X20 ST18000NM003D 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5' Internal Hard Drive (ST18000NM003D) is currently priced at $0.0353/GB ($635.00 for 18TB) 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.