Edited -- Divide the total number of users by the desired duration to determine the ramp-up rate. For example:

If you want to ramp up 100 users evenly over 1 minute:
Ramp-Up Period = Total number of users / Desired duration
= 100 users / 1 minute
= 100 users/minute
In this case, each user would start every 0.01 minutes (or every 0.6 seconds).

If you want to ramp up 100 users evenly over 5 minutes:
Ramp-Up Period = Total number of users / Desired duration
= 100 users / 5 minutes
= 20 users/minute
In this case, each user would start every 0.05 minutes (or every 3 seconds).

Consider Realistic Scenarios:
While evenly distributing users is a common approach, consider if it reflects the real-world usage pattern of your application. Sometimes, you might want to simulate a more gradual or sudden increase in load to mimic how users interact with the system.

Test Iteratively and Adjust as Needed:
It's essential to iterate on your load tests, adjusting parameters like the ramp-up period based on initial results. This iterative process helps refine the test plan to better simulate real-world scenarios and uncover performance bottlenecks.