1One click should open the phone dialler and input the number to be called.
2<a href="tel:5551234567">Call (555)123-4567</a>
1Area code with dashes, 1 and + sign
2
3<a href="tel:+1-555-555-1212">555-555-1212</a>
4Area code with no dashes, 1 and + sign
5
6<a href="tel:+15555551212">555-555-1212</a>
1<a href="tel:0123456789">Click to call</a>
2<!-- Adds country code with + -->
3<a href="tel:+0123456789">Click to call</a>
4<!-- Adds a 1 second pause (p) then dial 123 after phone number -->
5<a href="tel:0123456789p123">Click to call</a>