Multiply gigabytes by 1024 (binary)
GB to MB is a multiplication by 1000 in the decimal system. The gigabyte equals 10⁹ bytes; the megabyte equals 10⁶ bytes; the ratio is 10³, or exactly 1000. In the binary system the equivalent units are gibibyte (GiB, 2³⁰ bytes) and mebibyte (MiB, 2²⁰ bytes), giving a ratio of 1024. The IEC introduced the distinct binary prefixes in 1999 to end the GB/GiB ambiguity, but everyday vocabulary still uses 'GB' for both meanings depending on context.
The gigabyte-to-megabyte conversion is the everyday inverse of MB-to-GB. One gigabyte equals 1,000 megabytes under the decimal SI convention used by drive manufacturers, mobile carriers, and cloud providers.
Convert from GB to MB when comparing file sizes shown in different units, calculating how many MB-rated chunks fit in a GB-rated quota, or checking whether a file fits under an attachment limit. Binary contexts (RAM, certain older operating system displays) instead use 1 GiB = 1,024 MiB.
ConvertBuddy uses the decimal convention because that matches the labels on hard drives, the totals on mobile-plan invoices, and the units in cloud-storage billing.
A 1 GB folder cannot be sent as a single Gmail attachment (25 MB cap). Converting to MB makes the gap obvious: 1000 MB versus 25 MB → split into chunks or use a file-transfer service.
Apple iCloud, Google Photos, and OneDrive bill in GB but show per-photo sizes in MB. Convert to know how many photos a paid tier holds.
Premiere and Final Cut report timeline and proxy file sizes in MB. Project storage on shared NAS is allocated in GB. Convert to confirm a project fits its quota before render.
iOS Settings → Storage shows app caches in MB but device totals in GB. Converting helps decide whether deleting one big cache actually frees meaningful space.
Game patches list per-asset sizes in MB. Download caps on mobile plans run in GB. Convert to know whether a content update fits within the remaining monthly allowance.
4 GB equals 4,096 MB (binary).