1. I was going to buy a 1TB SSD. I ended up with a 4TB HDD.
What I originally wanted was a 1TB external SSD to plug into my M2 Mac over USB.
But once I looked at 2026 prices, a 1TB external SSD from a decent brand started at around 16,000 to 20,000 yen even at the cheap end. The well-known models that feel a bit safer cost even more. [1]
Then I looked at external hard drives (HDDs), and 4TB models start at about 20,500 yen. [2]
This is where the math gets weird.
1TB SSD: about 16,799 yen 4TB HDD: about 20,498 yen
The difference is about 3,700 yen.
For 3,700 yen more, you go from 1TB to 4TB. If you don't care about speed, that's a pretty strong deal.
The question of this article is simple.
If all you want is a place to park data you rarely touch (old articles, images, past projects, backups), is a 4TB HDD a smarter buy than a 1TB SSD?
My answer: if you're not carrying it around or editing video straight off the drive, it makes a lot of sense. Paying extra for SSD speed can actually be a mismatch for what you need.
2. Line up the prices and only the HDD capacity looks absurd
Here are fairly cheap, usable examples by capacity, as found on Kakaku.com (a Japanese price-comparison site) on September 1, 2026. The makers and series aren't the same across rows, so this isn't "one product in different sizes." It's a snapshot of where the market floor sat that day. [3][4][2][1][5][6]
| Type | Capacity | Street price | Per 1TB |
|---|---|---|---|
| HDD | 1TB | 12,028 yen | 12,028 yen |
| HDD | 2TB | 14,884 yen | 7,442 yen |
| HDD | 4TB | 20,498 yen | about 5,125 yen |
| SSD | 1TB | 16,799 yen | 16,799 yen |
| SSD | 2TB | 27,999 yen | about 14,000 yen |
| SSD | 4TB | 65,980 yen | 16,495 yen |
Here's the price gap as a rough bar chart. One block is about 2,000 yen.
HDD 1TB 12,028 yen ██████
HDD 2TB 14,884 yen ███████
SSD 1TB 16,799 yen ████████
HDD 4TB 20,498 yen ██████████
SSD 2TB 27,999 yen ██████████████
SSD 4TB 65,980 yen █████████████████████████████████
The funny part: a 2TB HDD is cheaper than a 1TB SSD.
And a 4TB HDD costs only about 3,700 yen more than a 1TB SSD while giving you four times the space. Compare 4TB to 4TB and it's 65,980 yen for the SSD versus 20,498 yen for the HDD. The SSD costs about 3.2 times as much. [2][6]
If you don't need speed, this is a completely different price world.
3. Why a 1TB HDD costs almost the same as a 2TB one
HDD prices aren't set only by how many terabytes are inside.
An external drive needs a case, a USB bridge board, a power supply, a cable, assembly, packaging, shipping and retail costs, and you need all of that whether it holds 1TB or 4TB.
So making the drive smaller doesn't cut the price in half just because the capacity is half.
In the cheap examples I found, 1TB is 12,028 yen and 2TB is 14,884 yen. For about 2,856 yen more, you get double the space. [3][4]
Going from 2TB to 4TB costs only about 5,614 yen more.
The HDD aisle is basically saying:
1TB: "That's 12,000 yen."
2TB: "Add about 3,000 and you get double."
4TB: "Add just over 5,000 and it doubles again."
The pricing nudges you toward the big sizes.
That's why, unless you're absolutely sure you only need 1TB, a 1TB HDD tends to look bad on price per terabyte.
4. If you don't use the speed, part of an SSD's price is a "performance you never use" fee
The strengths of an SSD are clear: fast reads and writes, no moving parts, and easy to carry around.
I/O Data, a Japanese storage maker, also explains the split this way: SSDs for work where efficiency matters, like editing and content creation, and HDDs for storing data. [7]
So what matters isn't which one is the "higher-end" product. It's what you'd actually be waiting on.
For example, SSD speed pays off if you:
- edit video on the external drive itself
- constantly read and write huge amounts of raw photos
- run virtual machines or games from an external drive
- do heavy, frequent builds of a large development environment
- copy hundreds of gigabytes every day
On the other hand, if you're just storing:
- Markdown files and article drafts
- old photos and videos
- finished projects
- materials you no longer use
- data you could download again
- files you don't want to delete but don't look at every day
then there's very little time in which you'd even feel the speed difference.
Article files are tiny. You don't need 1,000MB/s every time you open one.
If you don't need a fast warehouse, buy a big one.
5. Hunting for a rock-bottom SSD turned "cheap" into "more checking"
When SSDs feel too expensive, of course you start wondering whether there's a cheaper one.
That's where no-name external SSDs claiming to be 1TB, 4TB, 8TB or even 16TB for a few thousand yen show up. On Amazon, I found a 4TB listing with "256G expansion" written in the product name, and a listing selling 1TB for 2,000 yen. [8][9]
The reviews on the latter included several reports that the capacity shown and the capacity you can actually store were different.
One tool for testing such drives is F3. It writes test data to the drive, reads it back, and checks whether the advertised capacity really exists. [10]
Technically, that's fun.
But someone who simply wants storage isn't trying to play the fake-capacity lottery.
It might be 1TB for 5,000 yen
↓
When it arrives, test the whole drive
↓
If it's fake, send it back
↓
Look for the next one
By this point, I couldn't tell whether I was buying cheap storage or had taken an unpaid job in quality assurance.
A price so low that you have to test the drive before you can trust its capacity isn't cheap in practice.
After that detour, buying an ordinary HDD from a maker I'd actually heard of suddenly looked very appealing.
6. Why I finally picked a 4TB HDD for about 21,000 yen
21,000 yen isn't cheap.
In fact, it's the kind of price where you hesitate right when you're about to press the buy button.
Still, compare it with a 1TB SSD and the picture changes.
- Cheap usable 1TB SSD: about 16,799 yen
- Cheap usable 4TB HDD: about 20,498 yen
- Difference: about 3,699 yen
- Capacity: 4 times
If you need speed, buy the SSD.
If you don't, it's easier to think of it as paying 3,700 yen for an extra 3TB.
If several of your computers are running out of space and you want to move a pile of low-priority data out of the way, an extra 1TB fills up surprisingly fast. With 4TB, you can shove out everything you've decided you won't use right now in one go.
Funny how we'll happily pay for monthly subscriptions, but a 20,000-yen physical drive suddenly triggers a strict audit. People and their wallets are strange.
But once you count the time spent tidying up over and over because you're out of space, the 4TB was the better fit this time.
7. The cleanest setup: separate the "fast place" from the "roomy place"
You don't have to move everything to the HDD.
Keep the data you touch often on the Mac's internal SSD, and move only the big stuff you rarely open to the external HDD.
- Internal SSD: current articles, materials you use often, files you're working on
- 4TB HDD: past materials, finished data, large images and videos, low-priority files
Putting frequently used things in a fast place and rarely used things in a cheap, big place is a basic way of dividing up storage by role.
That way you spend SSD speed only where you really need it, and still get the HDD's low price per terabyte.
You don't need all SSD, and you don't need all HDD.
8. On a Mac, just watch the format and what "backup" really means
For a drive used only with a Mac, you can use APFS in Disk Utility. If you also want to share it with Windows, exFAT is an option. Apple says you can use APFS even on externally connected storage. [11]
You can also use an external HDD as a Time Machine backup disk. Apple says the ideal backup disk is at least twice the size of your Mac's storage. [12]
There's one important distinction, though.
If you move files from your PC to the HDD and then delete them from the PC, that isn't a "backup." It's just a change of storage location.
If that HDD dies, your only copy dies with it.
For things you'd be in real trouble to lose, like manuscripts, photos and important documents, keep one more copy on a separate physical drive, in the cloud, with Time Machine, or similar.
On the other hand, for low-priority data you could download again or lose without disaster, using a 4TB HDD just to free up space is useful enough.
9. Amazon or Rakuten? In the end, compare the total for the same model number
There's no fixed rule that Amazon or Rakuten (a big Japanese online mall) is always cheaper.
Even for the same model, the price on a given day, shipping, point rewards, sales and clearance deals can easily flip the result.
For storage like this, it's easier to first compare the same model number across sites such as Kakaku.com, and then check what you'd actually pay on Amazon and Rakuten. [2]
Rakuten in particular has days with big point rewards, while on Amazon the listed price is sometimes simply lower.
Rather than turning it into a store-versus-store contest, decide on the model you want and make them fight it out on that day's total price. That's the right way.
10. Conclusion: if you don't need speed, a 4TB HDD is a very strong pick
I started out looking for a 1TB SSD and landed on a 4TB HDD.
But line up the prices and it was actually the natural outcome.
In the street-price examples from September 1, 2026, a 1TB SSD was 16,799 yen and a 4TB HDD was 20,498 yen. For a difference of about 3,700 yen, you get four times the space. [2][1]
SSD speed is definitely valuable.
But that value is for people who use the speed.
If you're just storing lots of articles, images, finished data and things you might back up someday,
a roomy 4TB beats a fast 1TB.
And if you're eyeing rock-bottom no-name SSDs, worrying about fake capacity and even researching how to test for it, running off to a normal 4TB HDD makes life a lot more peaceful.
21,000 yen is a lot.
But if it also buys back all the time I'd spend asking "what do I delete?" every time I run out of space, then fine, it's worth it this time.
References (13)
- Kakaku.com, Verbatim Mini Stripe 32035-J 1TB external SSD (viewed 2026-09-01) kakaku.com
- Kakaku.com, ELECOM ELD-HTV040UBK 4TB HDD (viewed 2026-09-01) kakaku.com
- Kakaku.com (Japanese price-comparison site), list of 1TB external HDDs (viewed 2026-09-01) kakaku.com
- Kakaku.com, IODATA HDCZ-UT2KC 2TB HDD (viewed 2026-09-01) kakaku.com
- Kakaku.com, DIGIERA DGLPS2000MT02WH 2TB external SSD (viewed 2026-09-01) kakaku.com
- Kakaku.com, Silicon Power Stream S05 SP040TBPSDS05SAKTC 4TB external SSD (viewed 2026-09-01) kakaku.com
- I-O Data, differences between HDD, SSD and NAS and how to choose iodata.jp
- Amazon.co.jp, external SSD product page (ASIN B09NRC9Y57, checked 2026-09-01) amazon.co.jp
- Amazon.co.jp, external SSD product page (ASIN B0DQ3RMKKQ, checked 2026-09-01) amazon.co.jp
- F3 official repository github.com
- Apple Support, file system formats available in Disk Utility on Mac support.apple.com
- Apple Support, back up your Mac with Time Machine support.apple.com
- AKIBA PC Hotline!, SSD price trends (2023-03-23) akiba-pc.watch.impress.co.jp
