javascript to convert human readable bytes (eg 10MB) to a number (10,485,760)

human_readable_bytes_to_number.js

/**
 * Convert a string with B/K/M/etc into a byte number
 * @param  {String|Number} bytes Any string with B/K/M/etc
 * @return {String|Number}       A byte number, or original string as is
 */
function stringByteFormat(bytes)
{
	// if anything not string return
	if (!(typeof bytes === 'string' || bytes instanceof String)) {
		return bytes;
	}
	// for pow exponent list
	let valid_units = 'bkmgtpezy';
	// valid string that can be converted
	let regex = /([\d.,]*)\s?(eb|pb|tb|gb|mb|kb|e|p|t|g|m|k|b)$/i;
	let matches = bytes.match(regex);
	// if nothing found, return original input
	if (matches !== null) {
		// remove all non valid entries outside numbers and .
		// convert to float number
		let m1 = parseFloat(matches[1].replace(/[^0-9.]/,''));
		// only get the FIRST letter from the size, convert it to lower case
		let m2 = matches[2].replace(/[^bkmgtpezy]/i, '').charAt(0).toLowerCase();
		if (m2) {
			// use the position in the valid unit list to do the math conversion
			bytes = m1 * Math.pow(1024, valid_units.indexOf(m2));
		}
	}
	return bytes;
}

Because there are so many number to human readable bytes, but not a single one for the other way around.

Not if you send anything other in than string or int/float it will fail of course.