TBW
TBW, terabytes written, is an SSD maker's endurance rating: the total data the drive is warranted to accept over its life before wear may end it.
Also known as terabytes written, SSD endurance, endurance rating
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Flash cells wear out a little each time they are erased and rewritten, so every solid-state drive has a finite write life. Makers express it as terabytes written: a drive rated at a given TBW is warranted to accept that many terabytes of writes within its warranty period. Some enterprise drives quote drive writes per day instead, which is the same idea divided by capacity and warranty length. The warranty usually ends at whichever comes first, the years or the TBW.
For most home use the rating is far above what a drive will see, because ordinary use writes far less than a drive's capacity each day. It matters for heavy write workloads such as video capture, large scratch disks, databases and some game-download habits, and when comparing two drives of the same capacity on a maker's spec sheets. A higher TBW is not a speed figure and says nothing about how the drive performs.
A browser cannot read a drive's TBW, its model or how much has been written so far. The drive's own SMART data holds the running total, which CrystalDiskInfo on Windows, smartctl, or the maker's own tool can show; set that against the rating on the maker's spec sheet. The SSD spec sheet page lists which makers print the figure.
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