Seagate · Enterprise
ST18000NM004J
Exos X18 18TB
SAS 12 Gb/s · 3.5-inch
Exact Amazon US product
$599.00
View on Amazon US ↗New listing · ASIN B08NCF8Z8Q
Price as of Sep 12, 2026 11:45 UTC
The Seagate ST18000NM004J is a 18TB Exos X18 hard drive for server and enterprise storage, using SAS 12 Gb/s in a 3.5-inch form factor.

Manufacturer specifications
| Model number | ST18000NM004J |
|---|---|
| Nominal capacity | 18 TB · 18000 GB |
| RPM | 7200 |
| Interface | SAS 12 Gb/s |
| Cache (MB) | 256 |
| Form factor | 3.5-inch |
| Average idle power (W) | 5.6 |
| Power-on hours per year | 8760 |
| Manufacturer limited warranty | 5 years (eligible new drives) |
| Sustained transfer (up to MB/s) | 270 |
Source: Seagate Exos X18 manufacturer specifications, pages 2. Reviewed 2026-09-07. Published specifications, not our benchmark results.
What the specifications mean
- Up to 270 MB/s sustained transfer, as specified by the manufacturer. This is not a measured game-loading or random-I/O result.
Before ordering
Match ST18000NM004J, 18TB and SAS 12 Gb/s against the selected offer. Check your system’s exact-model compatibility list and the seller’s warranty and return terms.
Amazon US listings
Exact model matches on Amazon.com. A verified ASIN identifies the product; it does not guarantee current stock. Check the selected variant, condition and seller.
Amazon US · ASIN B08NCF8Z8Q
$599.00 · as of Sep 12, 2026 11:45 UTC
Amazon US · ASIN B08NCF8Z8Q
$582.00 · as of Sep 12, 2026 11:45 UTC
Amazon US · ASIN B0DMWT8MM7
Same-capacity alternatives with Amazon US links
These models share the drive type, interface class and capacity. Compare their specifications and your system requirements before choosing a replacement.
Seagate · Exos X20
ST18000NM000D
18TB · 12 Gb/s SAS
Compare with ST18000NM004J →View on Amazon US ↗ASIN B09MWKFG51 · Check price and conditionSeagate · Exos X18
ST18000NM005J
18TB · SAS 12 Gb/s
Compare with ST18000NM004J →View on Amazon US ↗ASIN B098YCXY22 · Check price and conditionST18000NM004J questions answered
What connection does ST18000NM004J need?
ST18000NM004J uses SAS 12 Gb/s. It needs a compatible SAS controller or backplane; a standard motherboard SATA port cannot run it.
How much usable space does ST18000NM004J provide?
Its nominal capacity is 18000 GB, approximately 16763.8 GiB before formatting. The filesystem, reserved space and any RAID redundancy reduce usable capacity further.
What warranty is listed for ST18000NM004J?
Manufacturer specification: 5 years (eligible new drives). A renewed, used, OEM or imported offer can have different coverage. Check the serial number and seller terms before buying.