Choose an external drive that fits the amount of data you need to protect, works with your computer and backup software, and suits where you will store it. Then make sure the backup runs regularly and test that you can restore files. No single drive guarantees that your data is safe, so keep another copy—ideally somewhere separate from the computer and drive.
1. Work out how much capacity you need
Estimate the total data you want to back up: photos, videos, documents, project files, and a system backup if you plan to include one. Add room for the files you expect to create before you next replace or expand the drive. There is no single capacity that suits everyone; the right choice depends on your files and how quickly they grow.
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Compare that estimate with the drive’s advertised capacity, but do not assume the full nominal terabytes will be available for files after formatting. For example, Seagate lists its Backup Plus Portable line in several capacities, with some cited models available up to 5 TB; availability and terms depend on the exact model. See Seagate’s Backup Plus Portable support information.
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2. Check the exact model’s connection and compatibility
Match the drive’s connector and included cable to your computer’s ports, and check that the interface works with your backup software. Do not rely on a family name or a retailer’s broad compatibility label: specifications can differ by model and SKU.
#1 Best Overall
- Easily store and access 2TB to content on the go with the Seagate Portable Drive, a USB external hard drive
- Designed to work with Windows or Mac computers, this external hard drive makes backup a snap just drag and drop
- To get set up, connect the portable hard drive to a computer for automatic recognition no software required
- This USB drive provides plug and play simplicity with the included 18 inch USB 3.0 cable
- The available storage capacity may vary.
As one model-specific example, WD’s cited My Passport guidance lists USB 3.2 Gen 1 and USB 2.0 compatibility, with transfer rates up to 5 Gb/s. It says the drive is formatted as NTFS out of the box and may need reformatting for macOS. Verify the specifications for the exact model you are considering, especially if you will use the same drive with both Windows and Mac computers. Check WD’s My Passport compatibility and format guidance.
3. Choose a form factor for where the drive will live
A portable USB drive is compact and convenient if you need to carry it or store it away from your computer. A desktop external drive is intended for a more stationary setup. This is a practical distinction, not evidence that one type is more reliable.
Rank #2
- Easily store and access 5TB of content on the go with the Seagate portable drive, a USB external hard Drive
- Designed to work with Windows or Mac computers, this external hard drive makes backup a snap just drag and drop
- To get set up, connect the portable hard drive to a computer for automatic recognition software required
- This USB drive provides plug and play simplicity with the included 18 inch USB 3.0 cable
- The available storage capacity may vary.
Wherever the drive is used, handle it carefully, avoid physical shocks, and provide stable temperatures and ventilation. Backblaze offers these as general handling recommendations; its guidance does not quantify how a particular household storage condition changes failure risk. Read Backblaze’s drive-care and reliability guidance.
4. Compare the features and terms that matter
For each exact model, check whether it includes encryption or backup software, what support is offered, and what the warranty covers in your region. A warranty is a support or replacement promise; it does not restore files that exist only on a failed drive.
Rank #3
- Easily store and access 1TB to content on the go with the Seagate Portable Drive, a USB external hard drive.Specific uses: Personal
- Designed to work with Windows or Mac computers, this external hard drive makes backup a snap just drag and drop. Reformatting may be required for Mac
- To get set up, connect the portable hard drive to a computer for automatic recognition no software required
- This USB drive provides plug and play simplicity with the included 18 inch USB 3.0 cable
- The available storage capacity may vary.
Specifications and coverage vary. WD says the cited My Passport family supports 256-bit AES hardware encryption and links to limited-warranty information. Seagate lists two-year limited warranties for particular Backup Plus Portable models. Confirm the current terms for the precise SKU and market rather than assuming they apply to every drive in either family. WD My Passport details; Seagate Backup Plus Portable details.
If you enable encryption, understand how the password or recovery process works before storing your only backup on the drive. Encryption can protect files if the drive is lost, but losing access credentials can also prevent you from reaching those files.
Rank #4
- Easily store and access 4TB of content on the go with the Seagate Portable Drive, a USB external hard drive.Specific uses: Personal
- Designed to work with Windows or Mac computers, this external hard drive makes backup a snap just drag and drop
- To get set up, connect the portable hard drive to a computer for automatic recognition no software required
- This USB drive provides plug and play simplicity with the included 18 inch USB 3.0 cable
- The available storage capacity may vary.
5. Read reliability statistics in context
Reliability figures describe the population and conditions measured, not a promise about an individual drive. Backblaze’s 2025 year-end report gives a 1.36% annualized failure rate (AFR) for 344,196 qualifying HDDs across 30 models in its data-center fleet. The report compares that with 1.55% in 2024. These are fleet-level figures, not consumer external-drive model scores or a prediction of how long a particular drive will last. The data does not test complete retail external-drive enclosures or establish a universal brand winner. Read Backblaze’s 2025 Drive Stats report.
Backblaze notes that “even drive models from the same manufacturer have variable reliability.” Its statistics can show how failure rates are measured and how models vary in its operating fleet, but they cannot identify a guaranteed-safe consumer choice. Backblaze’s explanation of drive reliability.
6. Make the drive part of a backup routine
A drive only protects files that have actually been copied to it. Connect it often enough for your chosen backup method to update, and periodically restore a few important files to check that the backup is usable. Keep a second copy in another location where practical: a drive beside the computer can be lost to the same theft, damage, or other event as the computer.
If you use Backblaze Computer Backup for files on an external drive, its retention rules are service-specific. Under its default 30-Day Version History, Backblaze says the external drive must reconnect at least once every 30 days to keep its data in the backup. With 1-Year Extended Version History, data from a disconnected drive is retained for up to one year. Backblaze also describes missing-drive alerts. Check its current settings and terms if you rely on this service; these rules do not apply to other backup providers. Read Backblaze’s external-drive backup documentation.
Quick Recap
A practical comparison checklist
- Capacity: Does it cover the data you need to protect and leave room for expected growth?
- Connection: Does the exact model include a cable and interface compatible with your computer?
- Format: Will its filesystem work with your operating system and any other computer that needs access?
- Storage location: Is a portable drive or a stationary desktop drive more suitable for your setup?
- Protection and recovery: Are encryption, password recovery, backup software, support, and warranty terms clear for the exact SKU?
- Evidence: Are reliability claims based on a relevant test or population, rather than being presented as a guarantee?
- Backup plan: How often will the drive be updated, and where will you keep another copy?
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
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