html input type phone number validation code example

Example 1: input type for contact no

label for="phone">Enter your phone number:</label>
<input type="tel" id="phone" name="phone" pattern="[0-9]{3}-[0-9]{2}-[0-9]{3}">

Example 2: phone number validation html

How about this? /(7|8|9)\d{9}/

It starts by either looking for 7 or 8 or 9, and then followed by 9 digits.