What is the difference between MB and MiB?

MB (megabyte) uses decimal: 1 MB = 1,000,000 bytes. MiB (mebibyte) uses binary: 1 MiB = 1,048,576 bytes. OS reporting differs — macOS and most modern tools use decimal, while some older Windows versions use binary.

Why are there two modes?

Hard drive manufacturers use decimal (a '1 TB' drive has 1,000,000,000,000 bytes), while RAM and some software report in binary. The converter supports both so you can compare accurately.

A petabyte is 1,000 terabytes in decimal or 1,125,899,906,842,624 bytes in binary. Modern hyperscale data centres measure storage in petabytes and exabytes.

Can I enter decimal values like 1.5 GB?

Yes. You can enter any decimal number and the converter will calculate all equivalent values with full precision.

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File Size Converter

Convert between file size units — bits, bytes, KB, MB, GB, TB, PB — in decimal (SI) and binary (IEC) modes.

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About this tool

Enter any file size in any unit and see all conversions update instantly. Switch between decimal (SI) mode where 1 KB = 1,000 bytes and binary (IEC) mode where 1 KiB = 1,024 bytes. A handy reference section shows real-world comparisons so you can put the numbers in context.

How to use

1 Type a number into any unit field (e.g. enter 5 in the MB box).
2 All other unit fields update automatically with the equivalent values.
3 Toggle between Decimal (SI) and Binary (IEC) mode using the radio buttons at the top.
4 Check the reference section at the bottom to compare your value to real-world file sizes.

Frequently Asked Questions

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