The Seagate IronWolf Pro, 20 TB, Enterprise NAS Internal HDD –CMR 3.5 Inch, SATA 6 Gb/s, 7,200 RPM, 256 MB Cache for RAID Network Attached Storage (ST20000NT001) costs $0.0335/GB while the WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black costs $0.0432/GB. Seagate IronWolf Pro, 20 TB, Enterprise NAS Internal HDD –CMR 3.5 Inch, SATA 6 Gb/s, 7,200 RPM, 256 MB Cache for RAID Network Attached Storage (ST20000NT001) offers 22% better value per gigabyte as of September 2026. Both products are available on BuyPerUnit with prices from Amazon, Best Buy, and Newegg.
Seagate IronWolf Pro, 20 TB, Enterprise NAS Internal HDD –CMR 3.5 Inch, SATA 6 Gb/s, 7,200 RPM, 256 MB Cache for RAID Network Attached Storage (ST20000NT001) vs WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black — Which Is Better Value?
WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black
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Specification Comparison
| Spec | Seagate IronWolf Pro, 20 TB, Enterprise NAS Internal HDD –CMR 3.5 Inch, SATA 6 Gb/s, 7,200 RPM, 256 MB Cache for RAID Network Attached Storage (ST20000NT001) | WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black |
|---|---|---|
| Brand | Seagate | Western Digital |
| Capacity | 20 TB | 18TB |
| $/GB | $0.0335 | $0.0432 |
| Price | $669.99 | $777.99 |
| Retailer | Amazon | 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 IronWolf Pro, 20 TB, Enterprise NAS Internal HDD –CMR 3.5 Inch, SATA 6 Gb/s, 7,200 RPM, 256 MB Cache for RAID Network Attached Storage (ST20000NT001) offers better value at $0.0335//GB compared to the WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black at $0.0432//GB — that's roughly 22% less per gigabyte.
The best deal for the Seagate IronWolf Pro, 20 TB, Enterprise NAS Internal HDD –CMR 3.5 Inch, SATA 6 Gb/s, 7,200 RPM, 256 MB Cache for RAID Network Attached Storage (ST20000NT001) is $669.99 at Amazon, while the WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black starts at $777.99 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 IronWolf Pro, 20 TB, Enterprise NAS Internal HDD –CMR 3.5 Inch, SATA 6 Gb/s, 7,200 RPM, 256 MB Cache for RAID Network Attached Storage (ST20000NT001) and WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black product page for detailed specifications and price history.
Frequently Asked Questions
Is Seagate IronWolf Pro, 20 TB, Enterprise NAS Internal HDD –CMR 3.5 Inch, SATA 6 Gb/s, 7,200 RPM, 256 MB Cache for RAID Network Attached Storage (ST20000NT001) or WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black a better deal?
As of September 2026, Seagate IronWolf Pro, 20 TB, Enterprise NAS Internal HDD –CMR 3.5 Inch, SATA 6 Gb/s, 7,200 RPM, 256 MB Cache for RAID Network Attached Storage (ST20000NT001) offers better value at $0.0335//GB compared to WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black at $0.0432//GB. That is approximately 22% better value per gigabyte.
What is the price per GB of Seagate IronWolf Pro, 20 TB, Enterprise NAS Internal HDD –CMR 3.5 Inch, SATA 6 Gb/s, 7,200 RPM, 256 MB Cache for RAID Network Attached Storage (ST20000NT001)?
The Seagate IronWolf Pro, 20 TB, Enterprise NAS Internal HDD –CMR 3.5 Inch, SATA 6 Gb/s, 7,200 RPM, 256 MB Cache for RAID Network Attached Storage (ST20000NT001) is currently priced at $0.0335/GB ($669.99 for 20 TB) at Amazon.
Where can I buy WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black for the cheapest price?
The cheapest price for the WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black is $777.99 at Newegg, which works out to $0.0432/GB.