Hi all, have come across a small issue with some code I'm writing. Basically my users will enter in a serial number (alphanumeric) and then specify a quantity to add. My code then takes this and increments from the original. I've had to consider a number of possible issues. Using the ++ operator the serial will increase, however if the number is quite large it then if converted to scientific notation. To give you an idea I type in: 04000000000000000001 (quantity of 3), so I'd expect to get: 04000000000000000002 04000000000000000003 However I'm getting: 0000000000000004E+18 0000000000000004E+18 [code] if ($increment == 1) { $serialCutEnd = preg_replace('/[0-9]*$/', '', $serial); $serialEnding = substr($serial, strlen($serialCutEnd)); [/code] This handles quite well but when the number gets big I run into trouble. Is there a way to force the value to remain a string? I've tried type casting but it seems as soon as I use the ++ operator issues arise. I'd appreciate any guidance on this. Cheers