(PHP 4, PHP 5)
decbin — Decimal to binary
$number
   )
   Returns a string containing a binary representation of the given
   number argument.
  
numberDecimal value to convert
| positive number | negative number | return value | 
|---|---|---|
| 0 | 0 | |
| 1 | 1 | |
| 2 | 10 | |
| ... normal progression ... | ||
| 2147483646 | 1111111111111111111111111111110 | |
| 2147483647 (largest signed integer) | 1111111111111111111111111111111 (31 1's) | |
| 2147483648 | -2147483648 | 10000000000000000000000000000000 | 
| ... normal progression ... | ||
| 4294967294 | -2 | 11111111111111111111111111111110 | 
| 4294967295 (largest unsigned integer) | -1 | 11111111111111111111111111111111 (32 1's) | 
| positive number | negative number | return value | 
|---|---|---|
| 0 | 0 | |
| 1 | 1 | |
| 2 | 10 | |
| ... normal progression ... | ||
| 9223372036854775806 | 111111111111111111111111111111111111111111111111111111111111110 | |
| 9223372036854775807 (largest signed integer) | 111111111111111111111111111111111111111111111111111111111111111 (63 1's) | |
| -9223372036854775808 | 1000000000000000000000000000000000000000000000000000000000000000 | |
| ... normal progression ... | ||
| -2 | 1111111111111111111111111111111111111111111111111111111111111110 | |
| -1 | 1111111111111111111111111111111111111111111111111111111111111111 (64 1's) | |
   Binary string representation of number
  
Example #1 decbin() example
<?php
echo decbin(12) . "\n";
echo decbin(26);
?>
The above example will output:
1100 11010