Generating a random hex color code with PHP

Question

I\'m working on a project where I need to generate an undefined number of random, hexadecimal color codes…how would I go about building such a function in PHP?

Answer 1

This is how i do it.

<?php echo 'rgba('.rand(0,255).', '.rand(0,255).', '.rand(0,255).', 0.73)'; ?>

Answer 2

Valid hex colors can contain 0 to 9 and A to F so if we create a string with those characters and then shuffle it, we can grab the first 6 characters to create a random hex color code. An example is below!

code

echo '#' . substr(str_shuffle('ABCDEF0123456789'), 0, 6);

I tested this in a while loop and generated 10,000 unique colors.

code I used to generate 10,000 unique colors:

$colors = array();
while (true) {
   $color          = substr(str_shuffle('ABCDEF0123456789'), 0, 6);
   $colors[$color] = '#' . $color;
   if ( count($colors) == 10000 ) {
      echo implode(PHP_EOL, $colors);
      break;
   }
}

Which gave me these random colors as the result.

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outis pointed out that my first example couldn't generate hexadecimals such as '4488CC' so I created a function which would be able to generate hexadecimals like that.

code

function randomHex() {
   $chars = 'ABCDEF0123456789';
   $color = '#';
   for ( $i = 0; $i < 6; $i++ ) {
      $color .= $chars[rand(0, strlen($chars) - 1)];
   }
   return $color;
}

echo randomHex();

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The second example would be better to use because it can return a lot more different results than the first example, but if you aren't going to generate a lot of color codes then the first example would work just fine.

Answer 3

function random_color(){  
 return sprintf('#%06X', mt_rand(0, 0xFFFFFF));
}

Answer 4

Shortest way:

echo substr(uniqid(),-6); // result: 5ebf06

Answer 5

I think this would be good as well it gets any color available

$color= substr(str_shuffle('AABBCCDDEEFF00112233445566778899AABBCCDDEEFF00112233445566778899AABBCCDDEEFF00112233445566778899'), 0, 6);

Answer 6

If someone wants to generate light colors

sprintf('#%06X', mt_rand(0xFF9999, 0xFFFF00));