If a gigabyte is 1024 megabytes and a kilobyte is 1024 bytes, a gigabyte is 1,073,741,824 bytes. This is slightly larger than 1,000,000,000 bytes, which is often used as an estimate for a gigabyte. For an explanation of why these units are sometimes multiplied by 1024 and not 1000, view this Help Center article.read more >>