Megabytes to gigabytes converter

Megabyte file sizes are useful for adding documents, photos or downloads before comparing them with a larger storage allowance. These are decimal MB. If a program reports MiB, select a binary conversion instead of assuming that a 1,024 multiplier applies here.

One megabyte is exactly 0.001 gigabytes. 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 megabytes by 0.001. For example, 1500 MB × 0.001 = 1.5 GB. To go the other way, divide by 0.001.

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, “1500 MB to GB” 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.