Can't set max date on date input

November 17, 2021

I am trying to set a min and max date to my date inputs, the min setting is working but for some reason the max date is not. What is the problem here?
I have also tried to use getDate()+90 instead of getMonth()+3.

my inputs:

let today = new Date().toISOString().split('T')[0];
let date3m = new Date(new Date().setDate(new Date().getMonth() + 3));
document.getElementsByName("start")[0].setAttribute('min', today);
document.getElementsByName("start")[0].setAttribute('max', date3m)

<div class="calendar">
  <div>
    <label for="start">Start Dato:</label>
    <input type="date" id="start" name="start" required>
  </div>
  <div>
    <label for="end">Slutt Dato:</label>
    <input type="date" id="end" name="end" required>
  </div>

</div>

>Solution :

min and max need to be in the format YYYY-MM-DD. You’re setting max to something like Sat Nov 13 2021 18:14:51 GMT-0500 (Eastern Standard Time), which doesn’t work.

Use toISOString() just like you do for today.

And setDate() should be setMonth().

let today = new Date().toISOString().split('T')[0];
let date3m = new Date();
date3m.setMonth(date3m.getMonth() + 3);
date3m = date3m.toISOString().split('T')[0];
document.getElementsByName("start")[0].setAttribute('min', today);
document.getElementsByName("start")[0].setAttribute('max', date3m)

<div class="calendar">
  <div>
    <label for="start">Start Dato:</label>
    <input type="date" id="start" name="start" required>
  </div>
  <div>
    <label for="end">Slutt Dato:</label>
    <input type="date" id="end" name="end" required>
  </div>

</div>