how to input double in a form code example

Example 1: input type that allows float number

<input type="number" step="0.01">

Example 2: how to write floating point numbers in html5 input

<form>
  <input type=number step=1 /> Step 1 (default)<br />
  <input type=number step=0.01 /> Step 0.01<br />
  <input type=number step=any /> Step any<br />
  <input type=range step=20 /> Step 20<br />
  <input type=datetime-local step=60 /> Step 60 (default)<br />
  <input type=datetime-local step=1 /> Step 1<br />
  <input type=datetime-local step=any /> Step any<br />
  <input type=datetime-local step=0.001 /> Step 0.001<br />
  <input type=datetime-local step=3600 /> Step 3600 (1 hour)<br />
  <input type=datetime-local step=86400 /> Step 86400 (1 day)<br />
  <input type=datetime-local step=70 /> Step 70 (1 min, 10 sec)<br />
</form>