how do i multiply small floats with an unkown number of decimal places in php without getting zero because of scientific notation?

Okay, I found a way to solve it, so, here’s how to multiply very small floating point numbers without needing to set an explicit scale for the numbers:

function getDecimalPlaces($value) {
// first we get how many decimal places the small number has
// this code was gotten on another StackOverflow answer

   $current = $value - floor($value);
   for ($decimals = 0; ceil($current); $decimals++) {
      $current = ($value * pow(10, $decimals + 1)) - floor($value * pow(10, $decimals + 1));
   return $decimals;

function multiplySmallNumbers($value, $smallvalue) {
   $decimals = getDecimalPlaces($smallvalue); // Then we get number of decimals on it
   $smallvalue = sprintf('%.'.$decimals.'f',$smallvalue ); // Since bcmul uses the float values as strings, we get the number as a string with the correct number of zeroes
   return (bcmul($value,$smallvalue));

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