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 Seagate One Touch STLC18000400 18 TB Hard Drive - 3.5' External - SATA (SATA/600) - Black - USB 3.0 Micro-B costs $0.0589/GB. Seagate Exos X20 ST18000NM003D 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5' Internal Hard Drive (ST18000NM003D) offers 40% 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 Seagate One Touch STLC18000400 18 TB Hard Drive - 3.5' External - SATA (SATA/600) - Black - USB 3.0 Micro-B — Which Is Better Value?
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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) | Seagate One Touch STLC18000400 18 TB Hard Drive - 3.5' External - SATA (SATA/600) - Black - USB 3.0 Micro-B |
|---|---|---|
| Brand | Seagate | Seagate |
| Capacity | 18TB | 18TB |
| $/GB | $0.0353 | $0.0589 |
| Price | $635.00 | $1061.08 |
| 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 X20 ST18000NM003D 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5' Internal Hard Drive (ST18000NM003D) offers better value at $0.0353//GB compared to the Seagate One Touch STLC18000400 18 TB Hard Drive - 3.5' External - SATA (SATA/600) - Black - USB 3.0 Micro-B at $0.0589//GB — that's roughly 40% less per gigabyte.
The best deal for the Seagate Exos X20 ST18000NM003D 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5' Internal Hard Drive (ST18000NM003D) is $635.00 at Newegg, while the Seagate One Touch STLC18000400 18 TB Hard Drive - 3.5' External - SATA (SATA/600) - Black - USB 3.0 Micro-B starts at $1061.08 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 Seagate One Touch STLC18000400 18 TB Hard Drive - 3.5' External - SATA (SATA/600) - Black - USB 3.0 Micro-B 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 Seagate One Touch STLC18000400 18 TB Hard Drive - 3.5' External - SATA (SATA/600) - Black - USB 3.0 Micro-B a better deal?
As of August 2026, Seagate Exos X20 ST18000NM003D 18TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5' Internal Hard Drive (ST18000NM003D) offers better value at $0.0353//GB compared to Seagate One Touch STLC18000400 18 TB Hard Drive - 3.5' External - SATA (SATA/600) - Black - USB 3.0 Micro-B at $0.0589//GB. That is approximately 40% 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 Seagate One Touch STLC18000400 18 TB Hard Drive - 3.5' External - SATA (SATA/600) - Black - USB 3.0 Micro-B for the cheapest price?
The cheapest price for the Seagate One Touch STLC18000400 18 TB Hard Drive - 3.5' External - SATA (SATA/600) - Black - USB 3.0 Micro-B is $1061.08 at Newegg, which works out to $0.0589/GB.