MB to GB Converter

Toggle between decimal (1000) and binary (1024) calculation to match your drive, cloud provider, or operating system display.

Enter amount in MB or MiB (we'll convert).

Pick decimal for disk labels, binary for OS values.

Key results

GB
GiB
MB (decimal)

Decimal interpretation

1 GB = 1000 MB

Bytes (× 10⁶)

Binary interpretation

1 GiB = 1024 MiB

Bytes (× 2²⁰)

Formulas

Decimal: GB = MB ÷ 1000

Binary: GiB = MiB ÷ 1024

1 MB (decimal) = 1,000,000 bytes

1 MiB (binary) = 1,048,576 bytes

If you’re comparing to a hard drive label or cloud storage plan, use decimal. If you’re matching what Windows, macOS, or Linux shows in “properties”, use binary.

MB to GB quick table (decimal)

MB GB (1000) GiB (1024)

Values rounded to 6 decimals.

Why two different ways?

Historically, computer memory grew in powers of 2, so using 1024 made sense (2¹⁰ = 1024). Storage manufacturers, however, followed SI prefixes: kilo = 1000, mega = 1,000,000, giga = 1,000,000,000. That’s why a “500 GB” drive shows about “465 GiB” on your computer.

Which one should I use?

  • Use decimal (1000) when talking about network, cloud, drive labels, subscriptions.
  • Use binary (1024) when matching OS-reported file sizes, RAM, or technical documentation that explicitly uses MiB/GiB.

FAQ

1. Is MB the same as MiB?

No. MB = 1,000,000 bytes, MiB = 1,048,576 bytes. They are close, but not identical.

2. Why is my 256 GB drive showing less?

Because 256 GB (decimal) = 256,000 MB, but your OS divides by 1024³ to get GiB, which gives a slightly smaller number.