How to Calculate the TBW (Terabyte Writes ) for SSD Drive?

Above is the formula for calculating the TBW (Terabyte Writes ) of SSD drive:

1, As know that there is a OP zone (Over-provisioning) in a SSD drive, it takes about 7% of the capacity, so the real capacity you could use is about 93%.

2, P/E cycles (write cycles), depending on the Nand flash type of your SSD, and according to the newest process of Nand, their P/E cycles are as following:

SLC: ≈ 60,000

MLC: ≈3,000

TLC: ≈1,000

3, WAF (Write amplification), the perfect WAF is 1, but actually there is no SSD supplier can achieve their WAF to "1" , there are many factors affect the WAF, usually we calculate with 1.5 times.

What’s more, it's easy for you to calculate the lifetime (how many years you can use) for your SSD drive:

Lifetime (years) = (TBW / Workload) / 365

*Workload: total GB written per day