Function to add dashes to US phone number in PHP

Question

What is the best way to add dashes to a phone number in PHP? I have a number in the format xxxxxxxxxx and I want it to be in the format xxx-xxx-xxxx. This only applies to 10 digit US phone numbers.

Answer 1

$number = "1234567890";
$formatted_number = preg_replace("/^(\d{3})(\d{3})(\d{4})$/", "$1-$2-$3", $number);

EDIT: To be a bit more generic and normalize a US phone number given in any of a variety of formats (which should be common practice - there's no reason to force people to type in a phone number in a specific format, since all you're interested in are the digits and you can simply discard the rest):

function localize_us_number($phone) {
  $numbers_only = preg_replace("/[^\d]/", "", $phone);
  return preg_replace("/^1?(\d{3})(\d{3})(\d{4})$/", "$1-$2-$3", $numbers_only);
}

echo localize_us_number("5551234567"), "\n";
echo localize_us_number("15551234567"), "\n";
echo localize_us_number("+15551234567"), "\n";
echo localize_us_number("(555) 123-4567"), "\n";
echo localize_us_number("+1 (555) 123-4567"), "\n";
echo localize_us_number("Phone: 555 1234567 or something"), "\n";

Answer 2

$number = '1234567890';
if(ctype_digit($number) && strlen($number) == 10) {
  $number = substr($number, 0, 3) .'-'.
            substr($number, 3, 3) .'-'.
            substr($number, 6);
}

Or if you for some reason want to avoid substr:

$number = '1234567890';
if(ctype_digit($number) && strlen($number) == 10) {
  $parts = str_split($number, 3);
  $number = $parts[0] .'-'. $parts[1] .'-'. $parts[3].$parts[4];
}

Answer 3

iterate through the string and make counter. When counter is 3 or 7 insert dash.

Answer 4

I feel obliged to post. Cheesiest solution:

$number = "1234567890";
$formatted_number = "$number[0]$number[1]$number[2]-$number[3]$number[4]$number[5]-$number[6]$number[7]$number[8]$number[9]";

But it works and its fast. vs. the preg_replace solution:

250,000 iterations:

preg_replace: 1.23 seconds ugly solution: 0.866 seconds

Pretty meaningless but fun :P

Answer 5

Here's what I used. It's not perfect, but it's an improvement over @Thilo's answer. It checks for a leading 1. If it's there, it ignores it. The code also ignores separating dashes, commas, and spaces, so it will work with 1231231234, 123 123 1234, and 123.123.1234. It doesn't handle numbers with parenthesis, but I'm sure there's another thread out there with that solution!

$formatted_number = preg_replace("/^1?(?:[- .])?(\d{3})(?:[- .])?(\d{3})(?:[- .])?(\d{4})$/", "($1) $2-$3", $not_formatted_phone_number);

Answer 6

A modification of Thilo's answer providing complete conditional formatting control over the leading "1".

public function phoneFormat($number) {
        $numbersOnly = preg_replace("/[^\d]/", "", $number);
        $nums = array_filter(explode("-", preg_replace("/^(1|)(\d{3})(\d{3})(\d{4})$/",
                                                            "$1-$2-$3-$4", $numbersOnly)));
        $output = $numbersOnly;
        if(count($nums) == 3){
            $output = "($nums[1])-$nums[2]-$nums[3]";
        }elseif(count($nums) == 4){
            $output = "$nums[0]-($nums[1])-$nums[2]-$nums[3]";
        }
        return $output;
  }

Answer 7

Here's what I came up with:

function format_phone($var_num) {
    $var_num = trim($var_num);
    $var_num = str_replace("(","",$var_num);
    $var_num = str_replace(")","",$var_num);
    $var_num = str_replace("-","",$var_num);
    $var_num = str_replace(" ","",$var_num);
    $var_num = str_replace(".","",$var_num);
    $var_num = substr($var_num, -10);
    $var_area_code = substr($var_num, 0, -7);
    $var_exchange = substr($var_num, 3, -4);
    $var_extention = substr($var_num, -4);
    $var_return = "{$var_area_code}-{$var_exchange}-{$var_extention}";
    return $var_return;
}

// Examples:
$phone_number = "1 (757) 555-1212";
// $phone_number = "17575551212";
// $phone_number = "(757) 555-1212";
// $phone_number = "757.555.1212";
echo "{$phone_number} = " . format_phone($phone_number);