How Disk Prices (US) Sorts Drives by Price per TB

Disk Prices (US) ranks storage listings by price per terabyte (price per TB), calculated as the listed price divided by the drive's capacity in terabytes. The site pulls listings from Amazon marketplaces and presents them in a sortable table, so the top of the list shows the cheapest storage per unit of capacity rather than the lowest sticker price. This matters because a $99 18 TB tape cartridge and a $100 2 TB flash card look similar in absolute cost but differ by roughly an order of magnitude in cost per TB.

How the metric is built

The calculation itself is simple division, but three inputs shape the result:

• Listed price — the current Amazon price for that listing, including multi-packs where the price covers the whole bundle.
• Capacity in TB — the drive's stated capacity, converted to terabytes so that GB- and TB-rated products compare on the same scale.
• Price per GB — the same figure divided by 1,000, shown alongside price per TB for finer-grained comparison between closely matched drives.

Because the site also displays capacity, warranty, form factor, technology, and condition as separate columns, you can see why a listing ranks where it does rather than trusting a single number.

A worked example from the listing data

The top of the table is dominated by LTO-9 tape media:

The $10 microSD listing and the $880 ten-pack of LTO-9 cartridges land at nearly the same price per TB despite a price difference of nearly two orders of magnitude. That is the core value of the sort: it strips out sticker price and exposes cost per unit of capacity.

Note also the multi-pack rows. An 18 TB ×10 pack is treated as 180 TB of total capacity against the bundle price, which is why bulk tape packs cluster near the top. If you only need one cartridge, the per-TB figure for the single-unit listing ($99 for 18 TB, about $5.50/TB) is the number to compare against.

Why sorting this way changes your decision

Lowest sticker price and lowest cost per TB often point to different products. Sorting by price per TB surfaces the second question — what am I paying for each terabyte? — which is usually the one that matters for bulk storage, backup targets, and archival media.

Two patterns follow from the data:

• High-capacity media tends to win on cost per TB. Tape and large hard drives spread their fixed costs over more capacity, so they rank above small flash cards even when the absolute price is higher.
• Small-capacity items can still compete. The 2 TB microSD at $10 shows that flash isn't automatically expensive per TB — but you are buying convenience and physical size, not bulk capacity.

The sort doesn't tell you which drive is right; it tells you which drive is cheapest per terabyte within whatever filters you've applied.

Using the filters to make the sort meaningful

A global price-per-TB ranking mixes tape, NVMe SSDs, memory modules, and optical media — categories that aren't substitutes for each other. The page provides filters that narrow the list before the sort does its work:

• Technology — Tape, Solid State, Hybrid, Rotational, Volatile (DDR4/DDR5 memory), Removable flash, Optical, and others.
• Form factor — External 3.5", External 2.5", Internal 3.5", Internal 2.5", M.2 SATA, M.2 NVMe, U.2/U.3, and tape generations LTO-3 through LTO-10.
• Condition — New or Used.
• Capacity range — set a minimum and maximum in GB or TB.
• Rotational and External toggles — quick switches for spinning disks and external enclosures.

A practical sequence: pick your technology and form factor first, set a capacity floor if you need a minimum size, then read the price-per-TB column top to bottom. Comparing an LTO-9 tape against an M.2 NVMe drive on price per TB is technically valid but tells you nothing useful about which to buy.

Reading the table columns

Each row carries the fields you need to sanity-check a ranking: price per GB, price per TB, absolute price, capacity, warranty (where listed), form factor, technology, condition, and the affiliate link to the Amazon listing. Warranty coverage varies by listing — some rows show two years, others show none — so check that column before treating a low per-TB figure as the final word.

Limits worth knowing

• Prices are Amazon listings, not a market index. They reflect what Amazon and its sellers charge at the time of the snapshot, and they change.
• Multi-pack pricing distorts per-unit intuition. A ten-pack's per-TB figure assumes you want all ten units; divide by unit count if you don't.
• The site is affiliate-supported. Links to Amazon are paid affiliate links, as stated on the page. That doesn't change the arithmetic, but it's the site's business model.
• Not every category is a like-for-like comparison. Memory modules (DDR4/DDR5) and optical media appear in the same table as drives; filter them out unless you're actually shopping for them.

The takeaway

Disk Prices (US) answers one question well: which storage costs least per terabyte? It computes price ÷ capacity in TB, displays price per GB alongside, and lets you filter by technology, form factor, condition, and capacity so the ranking compares things you'd actually consider buying. Use the filters to define your category, then read the price-per-TB column — and check capacity, warranty, and pack size before acting on the top row.