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Crucial
Model: CT4000X6SSD9
| Capacity | 4TB |
| Interface | USB 3.2 Gen 2 |
| Form Factor | External |
| Read Speed | 800 MB/s |
| Write Speed | 800 MB/s |
| Endurance (TBW) | 2,400 TB |
| Warranty | 3 Years |
A 4TB external at the X6's price is closer to spinning-rust economics than to typical SSD pricing. The 800 MB/s cap doesn't matter when the use case is video archive or photo-library cold storage — this drive is bought for capacity first, speed second.
See how it stacks up against competitors in our USB-C External SSDs SSD comparison, or browse related SSD buying guides.
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Reliable 4TB storage with 800 MB/s reads — the Crucial X6 4TB is a practical, affordable choice for daily backups and file transport.
With 800 MB/s reads and 800 MB/s writes over a USB-C connection, the Crucial X6 4TB delivers reliable performance for daily computing needs. Backing up documents, transferring photos from a laptop to a desktop, or storing a media library — it handles routine tasks with consistent speed.
4TB of storage provides generous headroom for everyday files. The compact, lightweight design slips into any bag pocket. 2,400 TBW endurance positions this as pro-grade — built for daily rewrite cycles without degradation. Backed by a 3-year warranty, this drive offers typical protection for its class.
4TB provides generous headroom for creative workflows — a working photo library, active video projects, and a game library all on one portable drive.
This speed range is typical of a SATA SSD running over USB — noticeably faster than any HDD, but well below what NVMe drives achieve over Gen 2x2 or Thunderbolt.
This drive performs like a SATA SSD over USB — roughly 5-6× faster than an external HDD for random reads, but not in the same league as NVMe-based externals. For documents, photos, and backups, the difference is academic.
The Crucial X6 4TB is a solid all-around 4TB portable SSD for everyday use. If you need fast backups, reliable file transport between devices, or external storage for documents, photos, and media, the 800 MB/s reads deliver performance that makes daily tasks feel instant compared to an external hard drive.
At 4TB, this drive hits the sweet spot for users with substantial storage needs. Photo and video libraries, game collections, and professional project files all benefit from the headroom — you will not be juggling free space or swapping files between drives.
The USB 3.2 Gen 2 interface means the Crucial X6 4TB hits full speed on virtually any modern USB-C or USB-A port — no special hardware required. Plug it into a laptop, desktop, game console, or tablet and you get the same 800 MB/s performance without compatibility concerns.
On paper, the Crucial X6 4TB delivers 800 MB/s reads and 800 MB/s writes. In practice, a 50GB file — a typical 4K video project, a large game install, or a full photo shoot — transfers in ~1 minutes. A 100GB batch of raw files moves in ~2 minutes. For users who regularly shuttle large files, these transfer times are a meaningful productivity improvement over slower SATA-based externals that take 3-5x longer for the same tasks. Note: those numbers describe large sequential transfers — everyday tasks (opening documents, app launches, game loads) feel equally fast across all NVMe portables because random 4K performance is similar drive-to-drive.
The Crucial X6 4TB is rated for 2,400 TBW (terabytes written) endurance. To put that in perspective: if you write 50GB per day — an aggressive daily workload for most users — the drive would take approximately 132 years to reach its endurance limit. For typical use patterns involving backups, file transfers, and game storage, the 2,400 TBW rating provides comfortable headroom well beyond the 3-year warranty period.
| Spec | Crucial X6 4TB | Samsung T9 2TB |
|---|---|---|
| Read Speed | 800 MB/s | 2,000 MB/s |
| Write Speed | 800 MB/s | 2,000 MB/s |
| Capacity | 4TB | 2TB |
| Interface | USB 3.2 Gen 2 | USB 3.2 Gen 2x2 |
| Endurance | 2,400 TBW | 1,200 TBW |
| Score | 8.2/10 | 9.6/10 |
The Samsung T9 2TB scores higher in our evaluation (9.6 vs 8.2/10). It also delivers faster reads (2,000 vs 800 MB/s).
For a detailed head-to-head comparison, see our full Crucial X6 4TB vs Samsung T9 2TB comparison.
| Model | Capacity | Interface | Read | Write | TBW |
|---|---|---|---|---|---|
| Crucial X6 4TB | 4TB | USB 3.2 Gen 2 | 800 | 800 | 2,400 |
| Samsung T9 2TB | 2TB | USB 3.2 Gen 2x2 | 2,000 | 2,000 | 1,200 |
| Samsung T9 Portable SSD | 1TB | USB 3.2 Gen 2x2 | 2,000 | 1,950 | 600 |
| Crucial X10 Pro 2TB | 2TB | USB 3.2 Gen 2x2 | 2,000 | 2,000 | 1,200 |
Specs shown for the closest USB-C External SSDs alternatives. Full comparison table available on the compare page.
The Crucial X6 comes in multiple capacities. Smaller sizes save money if you do not need the headroom; larger sizes drop the cost-per-TB for media libraries and Time Machine backups.
Crucial
Price as of Aug 3, 2026, 6:33 PM. Prices and availability are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply to the purchase of this product.
Crucial
Price as of Jul 3, 2026, 5:43 AM. Prices and availability are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply to the purchase of this product.
Crucial
Price as of Aug 3, 2026, 6:33 PM. Prices and availability are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply to the purchase of this product.
Crucial
Price as of Jul 3, 2026, 4:11 AM. Prices and availability are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply to the purchase of this product.