The Endurance Equation
SSD endurance is commonly described in terms of full Drive Writes Per Day (DWPD) for a certain warranty period (typically 3 or 5 years). In other words, if a 100GB SSD is specified for 1 DWPD, it can withstand 100GB of data written to it every day for the warranty period. Alternatively, if a 100GB SSD is specified for 10 DWPD, it can withstand 1TB of data written to it every day for the warranty period. Another metric that is used for SSD write endurance is Terabytes Written (TBW), which is used to describe how much data can be written to the SSD over the life of the drive. Again, the higher the TBW value, better the endurance of the SSD. What’s important to be careful about in this endurance specifications is the methodology used to determine these values. For example, the shorter the warranty period, the higher the DWPD will be for that specific SSD. Or larger the SSD drive capacity, higher the TBW for that specific SSD. In fact the JEDEC Solid State Technology Association’s standards subcommittee has now published two standards to help both SSD vendors and customers determine SSD endurance specifications for typical application usage.

Obviously, the higher the endurance the longer your drive will be able to operate and the more data it will be able to have written to it. Sounds simple enough, doesn’t it? The trick isn’t in searching out the biggest number, but rather in understanding what you need and finding the solution that meets those needs without over-buying.