Input form where all values have a default

Question

I am writing the UI for a tool that makes some plots (HTML here):

This program makes plots like this:

The input controls the limits of the axis, and the number of bins.

All of these fields (except Time axis max value) have a default value e.g. 0.0 for min value, 100 for number of bins, etc. The time axis max value, if left empty, will be the maximum time possible.

Do people have suggestions on how to deal with this? Should I use placeholders to let users know what the default value is? Should I pre-fill the fields with the default value instead?

Thanks

Answer 1

Don't use the placeholders for this valuable information because they cause accessibility and usability issues. I posted about this once so I won't repeat that here, but you can follow this link if you want to read more about it: Accessibility of in-field labels and help text labels in input forms

The input placeholders shown in the image are also misleading. The inputs are maybe optional but the value isn't. This causes a possible misconception for users. Make the fields mandatory to fill in and make users aware of what the default value is. To unburden users from having to fill in default values, the inputs should be pre-filled as you suggested yourself. But when they want to undo their input there must be a way to do so. You can either...

1. simply show the default. Pro: It is clear what the default value was if this matters for users. Con: The value has to be filled in manually.

2. provide an undo function. Pro: If the value isn't important to know, it can at least be easily reset. Con: The default value is not visible which can lead to an unwanted value in the input.

3. show the default and provide an undo function. Pro: Best of both options above. Con: This can either be unclear for users or to make it clearer a longer description will be needed which requires more space.