What is the proper, universal format for creating a clickable hyperlink for users on mobile devices to call a phone number?
Area code with dashes
<a href="tel:555-555-1212">555-555-1212</a>
Area code with no dashes
<a href="tel:5555551212">555-555-1212</a>
Area code with dashes and 1
<a href="tel:1-555-555-1212">555-555-1212</a>
Area code with no dashes and 1
<a href="tel:15555551212">555-555-1212</a>
Area code with dashes, 1 and + sign
<a href="tel:+1-555-555-1212">555-555-1212</a>
Area code with no dashes, 1 and + sign
<a href="tel:+15555551212">555-555-1212</a>
I also found this format online, and used it. Seems to work with or without dashes. I have verified it works on my Mac (tries to call the number in FaceTime), and on my iPhone:
<!-- Cross-platform compatible (Android + iPhone) -->
<a href="tel://1-555-555-5555">+1 (555) 555-5555</a>
I used:
Tel: <a href="tel:+123 123456789">+123 123456789</a>
and the result is:
Tel: +123 123456789
Where "Tel:" stands for pure text and only the number is coded and clickable.
-
doesnt make matter but +
sign is important when mobile user is in roaming
this is the standard format
<a href="tel:+4917640206387">+49 (0)176 - 402 063 87</a>
You can read more about it in the spec, see Make Telephone Numbers "Click-to-Call".
You can also use callto:########### replacing the email code mail with call, at least according to W3Cschool site but I haven't had an opportunity to test it out.
Source: Stackoverflow.com