Scale to select time period - linear or exponential?

Question

in my app, I need to allow customers to select a period of time between 15 minutes to up to 24 hours.

Now, I'm a bit confused of which is the best way to create a scale, linear or exponential.

The linear scale is simple, it will be a scale from 0 to 24 with 0.15 as step value.

The exponential one will be a bit different (not 100% sure yet, if you have any suggestion on this as well, feel free to write them down as well even if it's not the real question)

I was thinking about having the scale behave like the following:

0
0.15
0.30
0.45
1
1.30
2
2.30
3
3.30
4
4.30
5
6
7
8
9
10
12
14
16
18
20
22
24

But to be honest, I don't know how user usually reacts to exponential scale and I also don't know if they are good for selecting time periods.

So the question is: Linear or Exponential? which scale is better for this?

Thanks for any suggestion and feedback

Answer 1

A pure guess based on the limited info in your question: it looks like you're trying to use a dropdown or some other list based selector for this.

A more simple side-step to the linear/exponential question may be to offer two dropdowns: one for hours and another for quarter hours.

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