Check out example codes for "input type=number 01". It will help you in understanding the concepts better.

Code Example 1

<!--How to make a number field with always 2 numbers displayed : 01, 02, 03 ...-->
<input id="" type="number" min="1" max="99" step="1" onchange="if(parseInt(this.value,10)<10)this.value='0'+this.value;" />

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