Change datetime-local from 12h clock to 24h clock (beginner html/javascript)

[c0d0ps]

Hi I'm using a .html file

languages: html, JavaScript
level: beginner

Problem:
I am trying to change from 12h clock to 24h clock 
Background-info:
I am making a website to list attendance 

HTML code

<input type="datetime-local" id="inskrivningD" name="inskrivningD"
        min="10:00" max="15:01" required>
        <br>
        <small>
            Arbetstider är mellan 10am till 3:01pm (random swe text)
        </small>
        <br>
        <input type="submit">

 

[jj9987]

The format is chosen based on the client's browser and system settings. If you want to change it, you need to build your own.