# Megabytes to gigabytes converter

> Convert megabytes to gigabytes (MB to GB) with the exact factor, a conversion chart and worked steps.

Interactive version: https://www.calcopenly.com/conversion/mb-to-gb
Subject: Unit converters

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, so 1500 MB is 1.5 GB. To convert MB to GB, multiply by 0.001; to convert back, multiply by 1,000.

Storage makers use decimal prefixes, so 1 GB is 1,000 MB; some operating systems report binary units (1 GiB = 1,024 MiB). Because both units are defined exactly, the factor above is exact and the results here carry no conversion error.

## Inputs

- **Megabytes (MB)**

## Results

- Gigabytes (GB) — main result
- Conversion
- 1 GB in megabytes (MB)

## Formula

$$
\text{gigabytes} = \text{megabytes} \times 0.001
$$

## Worked examples

### 1500 MB to GB

- Megabytes (MB): 1500 MB
- **Gigabytes: 1.5 GB**
- Checked against: Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions)

### 750 MB to GB

- Megabytes (MB): 750 MB
- **Gigabytes: 0.75 GB**
- Checked against: Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions)

### 5000 MB to GB

- Megabytes (MB): 5000 MB
- **Gigabytes: 5 GB**
- Checked against: Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions)

## Questions

### When would I convert MB to GB?

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.

### How many gigabytes are in a megabyte?

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).

### How do you convert MB to GB?

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.

### Why does my computer show less space than the drive's label?

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).

### How accurate is the megabytes to gigabytes converter?

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).

### Where does the method come from?

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.

## Sources

- [NIST SP 811 (2008), Guide for the Use of the International System of Units, Appendix B](https://www.nist.gov/pml/special-publication-811)
- [NIST Handbook 44, Appendix C: General tables of units of measurement](https://www.nist.gov/pml/weights-and-measures/publications/nist-handbooks/handbook-44)
- [BIPM, The International System of Units (SI Brochure), 9th edition](https://www.bipm.org/en/publications/si-brochure)