What format should I use for an external hard drive?

For a drive you want to use across both Windows and Mac, exFAT is the easy choice, since both read and write it natively. If you only use Windows, NTFS is great. If you only use a Mac, the Mac format is best. Pick based on which machines will touch the drive.

What is exFAT and why use it?

exFAT is a cross-platform format that both Windows and Mac can read and write without extra software. That makes it the go-to for portable drives that move between different computers, or for sharing files with other people.

Should I use NTFS or exFAT?

Use NTFS if the drive lives on Windows machines only, since it is robust and well supported there. Use exFAT if the drive needs to work on both Windows and Mac. The right pick is simply about which systems will use the drive.

What Format Should You Use for an External Drive?

Published: August 15, 2026

Live answer · Amazon.com

Pulling live prices…

Live data across PricePerGig listings. Prices may change; Updated every few hours.

📊 As of 25 August 2026, the typical HDD on Amazon.co.uk is £160/TB or £0.16/GB across the 3,648 live listings we track, with the widest choice of drives priced around £44.6/TB or £0.045/GB. The best deals on Amazon.co.uk start from about £285 for 8TB (£35.6/TB), £332 for 14TB (£23.7/TB) and £652 for 20TB (£32.6/TB). The current best value is 14TB at roughly £23.7 per TB.

Sourced from real discussions on r/techsupport and r/DataHoarder, cross-checked against live PricePerGig listings.

Bought a new external drive and the format question is stumping you? It is simpler than it looks, and it comes down to one thing: which computers will use it.

Quick answer. Need it on both Windows and Mac? Use exFAT. Windows only? NTFS. Mac only? The Mac format.

That is genuinely most of the decision. Let me fill in the why.

The table above shows the live price per TB on your marketplace for the drive you are about to format.

exFAT: the cross-platform peacemaker

This is the one to reach for when a drive needs to travel between different computers.

exFAT is read and written natively by both Windows and Mac, with no extra software. Plug it into either, and it just works.

So exFAT is perfect for:

A portable drive you use on both a PC and a Mac.
A drive you share files with other people on.
Anything that moves around between machines.

If in doubt and you want maximum compatibility, exFAT is the safe, easy default.

NTFS: the Windows workhorse

If the drive will only ever touch Windows machines, NTFS is the better pick.

It is robust, handles large files and drives effortlessly, and is the format Windows itself uses. For a backup drive or storage drive that lives on your PC, NTFS is solid and dependable.

The catch is that Macs can read NTFS but not easily write to it without extra software. So NTFS is great for Windows-only life, less so if a Mac needs to save to it.

The Mac format: for Apple-only drives

If the drive will only ever be used with a Mac, use the Mac’s own format.

It is the most reliable choice for Time Machine backups and general Mac use, and it integrates perfectly with the system.

Just know that Windows cannot easily read the Mac format, so this is for Apple-only drives. If a PC ever needs in, you want exFAT instead.

A quick word on large files

One small gotcha to avoid.

There is an older format, sometimes the default on cheap drives, that cannot store single files bigger than four gigabytes. That is a problem for big videos and disk images.

So if your drive came preformatted and chokes on a large file, reformat it to exFAT or NTFS, which handle huge files without complaint.

The bottom line

The best format for an external drive depends only on which machines will use it. exFAT for cross-platform Windows and Mac, NTFS for Windows only, and the Mac format for Apple only.

Pick the one that matches your computers, avoid the old four-gigabyte-limited format, and your drive will just work. Grab a good value drive from the live prices above, format it right, and get on with storing your stuff.

exFAT: the cross-platform peacemaker

NTFS: the Windows workhorse

The Mac format: for Apple-only drives

A quick word on large files

The bottom line

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