How to calculate percentage improvement in response time for performance testing

Question

How should I calculate the percentage improvement in response time.

I am getting 15306 ms response time for old code and 799 ms response for th

Answer 1

Actually performance is about how much can be done in the same amount of time.

So the formula is OLD/NEW - 1 In your case your performance increased by 1816% (i.e. you can do 18.16X more in the same time)

15306/799 - 1 = 1816%

Note: before you could do 1/15360, now 1/799 ...