Gigabytes to megabytes converter

Gigabytes may describe a data plan, a collection of files or a drive partition. Converting that allowance helps compare it with a differently labelled quota. Keep decimal GB separate from GiB and distinguish storage capacity from a transfer rate.

One gigabyte is exactly 1,000 megabytes. Storage makers use decimal prefixes, so 1 GB is 1,000 MB; some operating systems report binary units (1 GiB = 1,024 MiB).

Multiply the number of gigabytes by 1,000. For example, 2 GB × 1,000 = 2,000 MB. To go the other way, divide by 1,000.

Drive makers count 1 GB as 1,000,000,000 bytes, while Windows and some other systems count in binary units of 1,073,741,824 bytes but still label them GB. A 1 TB drive therefore appears as about 931 GB (really 931 GiB).

Accuracy depends on your inputs and the method's assumptions. Decimal arithmetic uses 50 significant digits, but estimates, numerical methods and source data can be less precise; the displayed rounding does not remove those limits. It is checked against 3 worked examples whose answers come from independent sources; for example, “2 GB to MB” is checked against Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions).

NIST SP 811 (2008), Guide for the Use of the International System of Units, Appendix B; NIST Handbook 44, Appendix C: General tables of units of measurement; BIPM, The International System of Units (SI Brochure), 9th edition.