Gigabytes to Megabytes Converter

The converter above is already set to gigabytes and megabytes, so you only need to enter your number. The result updates as you type, and nothing is sent anywhere.

1. Type your value in the Value box, for example 4. Decimals and negative numbers are accepted.
2. Check that From shows gigabytes and To shows megabytes. Both menus can be changed if you need a different pair.
3. Read the answer in the large result box. The note under it shows the exact factor used for one gigabyte.
4. Press Copy result to put the answer on your clipboard, or Swap units to convert in the opposite direction.
5. Look at In every unit on the right to see the same amount in all the other data size units.

One gigabyte is exactly 1,000 megabytes, so the formula is megabytes = gigabytes x 1,000. Going the other way, one megabyte is exactly 0.001 gigabytes. In this converter a gigabyte is 1,000,000,000 bytes, the decimal convention used by drive makers and mobile carriers. In this converter a megabyte is 1,000,000 bytes, the decimal convention used by drive makers and mobile carriers.

Worked examples with the same factor:

• 4 gigabytes: 4 x 1,000 = 4,000 megabytes
• 10 gigabytes: 10 x 1,000 = 10,000 megabytes
• 40 gigabytes: 40 x 1,000 = 40,000 megabytes

Multiply by 1,000: 4 GB is 4,000 MB in decimal units, while an operating system that counts in 1,024s reports 4,096 MiB.

To check the converter by hand, take 10 gigabytes and apply the rule once: the result should be 10,000 megabytes. If you go back again with the reverse factor 0.001 you land on 10 gigabytes, which confirms that the two directions agree. Rounding the factor to fewer digits for mental math gives a result that is close but not identical, so use the tool when the last digits matter.

These reference values come from the same factor the converter uses, so they match what you see above. Use the table for common amounts, and the converter for anything else.

Computer storage is counted in two ways. The decimal convention used by drive makers, mobile carriers and this converter treats a kilobyte as 1,000 bytes and a gigabyte as one billion. The binary convention used by some operating systems treats a unit as 1,024 times the one before it, and properly calls the units kibibytes, mebibytes and gibibytes. Both are valid, but mixing them explains why a new drive looks smaller than advertised.

Use the table as a sanity check rather than a substitute for the converter. A typical phone photo is a few megabytes, a song is about 3 to 10 megabytes, a standard definition movie is around 1 to 2 gigabytes and a high definition movie is several gigabytes. If your file size comes out in a wildly different range, check whether you typed bytes, bits or a different multiple.

Mobile data allowances, uploads and game downloads quote gigabytes, while individual files are in megabytes.

Storage is sold in decimal units (1 GB is 1,000 MB) while many operating systems report binary units (1 GiB is 1,024 MiB), which is why a new drive shows less space than the label. This page uses the decimal units. The data size converter also lists the binary ones.

Related pages: Megabytes to Gigabytes Converter for the reverse direction, and the gigabytes to terabytes pages. For other data size units use the data size converter.

The page keeps no history, so each visit starts again from the defaults, 4 gigabytes. Your numbers are processed by JavaScript in your own browser and are never sent to a server, which makes the converter safe for private figures such as medical, financial or work measurements.