The WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black costs $0.0432/GB while the Seagate Expansion Desktop 16TB External Hard Drive – USB 3.0, 3.5" HDD for Windows & Mac, Plug-and-Play Backup Storage - STKP16000400 costs $0.0385/GB. Seagate Expansion Desktop 16TB External Hard Drive – USB 3.0, 3.5" HDD for Windows & Mac, Plug-and-Play Backup Storage - STKP16000400 offers 11% better value per gigabyte as of September 2026. Both products are available on BuyPerUnit with prices from Amazon, Best Buy, and Newegg.
WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black vs Seagate Expansion Desktop 16TB External Hard Drive – USB 3.0, 3.5" HDD for Windows & Mac, Plug-and-Play Backup Storage - STKP16000400 — 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 | WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black | Seagate Expansion Desktop 16TB External Hard Drive – USB 3.0, 3.5" HDD for Windows & Mac, Plug-and-Play Backup Storage - STKP16000400 |
|---|---|---|
| Brand | Western Digital | Seagate |
| Capacity | 18TB | 16 TB |
| $/GB | $0.0432 | $0.0385 |
| Price | $777.99 | $616.37 |
| Retailer | Newegg | Amazon |
| Category | Hard Drives (HDD) | Hard Drives (HDD) |
| Subcategory | hdd | hdd |
Price Across Retailers
Which Should You Buy?
Based on current pricing data, the Seagate Expansion Desktop 16TB External Hard Drive – USB 3.0, 3.5" HDD for Windows & Mac, Plug-and-Play Backup Storage - STKP16000400 offers better value at $0.0385//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 11% less per gigabyte.
The best deal for the Seagate Expansion Desktop 16TB External Hard Drive – USB 3.0, 3.5" HDD for Windows & Mac, Plug-and-Play Backup Storage - STKP16000400 is $616.37 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 WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black and Seagate Expansion Desktop 16TB External Hard Drive – USB 3.0, 3.5" HDD for Windows & Mac, Plug-and-Play Backup Storage - STKP16000400 product page for detailed specifications and price history.
Frequently Asked Questions
Is WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black or Seagate Expansion Desktop 16TB External Hard Drive – USB 3.0, 3.5" HDD for Windows & Mac, Plug-and-Play Backup Storage - STKP16000400 a better deal?
As of September 2026, Seagate Expansion Desktop 16TB External Hard Drive – USB 3.0, 3.5" HDD for Windows & Mac, Plug-and-Play Backup Storage - STKP16000400 offers better value at $0.0385//GB compared to WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black at $0.0432//GB. That is approximately 11% better value per gigabyte.
What is the price per GB of WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black?
The WD My Book 18TB USB 3.0, Micro-B External Desktop Hard Drive Black is currently priced at $0.0432/GB ($777.99 for 18TB) at Newegg.
Where can I buy Seagate Expansion Desktop 16TB External Hard Drive – USB 3.0, 3.5" HDD for Windows & Mac, Plug-and-Play Backup Storage - STKP16000400 for the cheapest price?
The cheapest price for the Seagate Expansion Desktop 16TB External Hard Drive – USB 3.0, 3.5" HDD for Windows & Mac, Plug-and-Play Backup Storage - STKP16000400 is $616.37 at Amazon, which works out to $0.0385/GB.