SSD TBW Calculator

TBW — Terabytes Written — is the number manufacturers use to describe how much data an SSD is rated to endure over its life. It’s printed on spec sheets and packaging, but it’s easy to misread or ignore entirely when comparing drives. This tool helps you work with a TBW figure directly: what it implies about a drive, and how to put it in context against your own usage.

What the Result Means

Enter a drive’s TBW rating along with an estimate of your daily write volume, and the calculator converts that rating into an estimated number of years before the drive reaches its endurance threshold. The point of this page isn’t just the number — it’s understanding what TBW is actually telling you when you’re shopping for a drive or evaluating the one you already own.

TBW is an endurance rating, not a speed or capacity spec. Two drives with identical capacity and price can carry very different TBW numbers depending on the type and quality of NAND flash used, the amount of spare area reserved for wear-leveling, and the controller’s efficiency. A higher TBW at the same capacity generally signals a more durable drive, which matters more for write-heavy workloads (video editing, virtual machines, torrent seeding, logging/caching) than for typical browsing and gaming.

How This Calculator Works

Where to find TBW and how to use it:

1. Look up the TBW figure on the manufacturer’s product page or spec sheet — it’s usually listed alongside the warranty terms, since the two are tied together (whichever limit is hit first ends the warranty).
2. If TBW isn’t listed directly, some manufacturers instead publish a DWPD (Drive Writes Per Day) figure. You can convert it: DWPD × capacity (GB) × warranty period (days) = TBW in GB.
3. Compare that TBW figure against your own estimated daily writes to see how it translates into real-world years, rather than treating the raw number in isolation.

Worked example — converting DWPD to TBW: a drive rated at 0.3 DWPD, 2TB capacity, 5-year warranty:

• 0.3 DWPD × 2,000GB = 600GB written per day (rated)
• 5-year warranty ≈ 1,825 days
• 600GB × 1,825 days = 1,095,000GB = 1,095TBW

That single converted number is far easier to compare against a competing drive’s published TBW than trying to mentally combine DWPD, capacity, and warranty length every time.

Important Limitations

• TBW isn’t comparable across different capacities of the same rating language. A “600TBW” 1TB drive and a “600TBW” 2TB drive are not equally durable per gigabyte — always check TBW alongside capacity, ideally as a TBW-per-terabyte figure.
• Marketing pages sometimes omit TBW entirely. If you can’t find it on the main product page, check the full spec sheet, datasheet PDF, or a major retailer’s spec tab — it’s a required disclosure for most reputable brands.
• TBW doesn’t capture every failure mode. Controller defects, firmware bugs, and power-loss issues can end a drive’s life independent of how much data has been written to it.
• Enterprise and consumer TBW aren’t directly comparable in intent. Enterprise drives are rated for sustained heavy write workloads (often expressed in DWPD) and priced accordingly; comparing a consumer drive’s TBW against one isn’t a fair likefor-like check for typical home use.