At a glance
- Format written
tel:followed by the number- Number cleaning
- Spaces, brackets, dashes and dots are removed
- Plus sign
- Added when the number starts with neither + nor 0
- Error correction
- Level M
Fields
Phone Number Required
Use the full international form, with the country code, so it works for callers from other countries. With the field empty, Generate does nothing.
What the code contains
Typed as +1 (555) 123-4567
tel:+15551234567
Typed as 0300 1234567, a local number
tel:03001234567
Typed as 15551234567, with the country code but no plus
tel:+15551234567
A number starting with 0 is kept as a local number, which only dials correctly from inside that country.
What it does not do
- It never dials by itself; the phone waits for the caller to press call.
- It cannot add an extension reliably. Print the extension next to the code.
What we tested
We typed the same kind of number five ways into the live generator and decoded each code it drew.
| You type | The code contains |
|---|---|
+1 (555) 123-4567 | tel:+15551234567 |
15551234567 | tel:+15551234567 |
0300 1234567 | tel:03001234567 |
555.123.4567 | tel:+5551234567 |
+1 555 123 4567 ext 22 | tel:+15551234567 |
The first two are correct. A plain digit string gets a plus in front, which is right when it already starts with the country code. The last two show the mistakes below, and the tool now warns about both.
Common mistakes
A US number without the 1
Typed as 555.123.4567, the tool adds a plus and the code dials +5551234567. That is read as an international number, not a US one, so the call fails. The tool cannot know your country, so it does not guess. It shows this note instead: No country code? If this is a US or Canada number, type +1 first, or the code may dial the wrong number.
Writing the extension into the number
Phones handle extensions in a code differently, and many drop them or fail to dial. So the tool leaves the extension out: typed as +1 555 123 4567 ext 22, the code holds tel:+15551234567 and the page says: The extension was left out of the code. Print it next to the code instead.
Using a local number on something people take home
A number starting with 0 only dials correctly inside that country. For flyers, business cards and anything that may travel, use the international form.
Questions
Does scanning the code call the number straight away?
No. The phone opens its dialler with the number filled in and waits for the person to press call.
Can one code hold two numbers?
No, one code holds one number. For several numbers, a vCard code or a link to a contact page works better.
How big should I print it?
Our test number made a 25 × 25 grid, so 20 mm (0.8 in) is enough. Phone codes are short and among the easiest to scan.