Data Size Converter
Runs locally in your browser. Nothing leaves your device.Instantly convert data sizes between bits, bytes, MB, GB, MiB, GiB, and other SI and IEC units.
Use a comma or period as the decimal separator; do not use thousands separators.
All units
Base units
Decimal (SI) - bytes
Binary (IEC) - bytes
Decimal (SI) - bits
Binary (IEC) - bits
How it works
- 1
Enter value and source unit
Enter the data size value and choose the source unit, such as MB or MiB.
- 2
Choose the target unit
Choose the target unit, even across the decimal and binary systems.
- 3
Copy the result or swap units
Copy one or all results, or swap the source and target unit for the next conversion.
Good to know
The data size converter converts directly in your browser between base units, decimal SI units (bit and byte), and binary IEC units (bit and byte). A note explains the key difference: GB uses the decimal system (1 GB = 1,000,000,000 B), while GiB uses the binary system (1 GiB = 1,073,741,824 B).
Calculation runs locally in the browser. Operating systems, drive manufacturers, and software sometimes show storage sizes in GB (decimal) and sometimes in GiB (binary) — which explains why a “1 TB” drive often shows as smaller in the operating system.
Typical use cases
Understand drive and cloud storage capacity
Convert between GB and GiB to understand why a purchased drive shows as smaller in the operating system than advertised.
Convert file sizes for uploads and attachments
Convert MB to KB or bytes to compare file or attachment sizes against service or mailbox limits.
Technically compare RAM and memory specs
Use binary IEC units (KiB, MiB, GiB) when RAM or technical specs actually mean powers of two, instead of assuming decimal SI units.
Tips for better results
Deliberately distinguish GB and GiB
1 GB (decimal) equals 1,000,000,000 bytes, 1 GiB (binary) equals 1,073,741,824 bytes — the difference grows with scale and explains apparently “missing” storage.
Don't confuse bit and byte
Network speeds are often given in bits, file sizes in bytes — one byte equals 8 bits, which is easy to overlook in conversions.
Features
SI and IEC units separated
Decimal SI units and binary IEC units for bit and byte are cleanly separated.
Local conversion
Calculation happens directly in the browser, without transmission to a server.
Built-in GB-vs-GiB explanation
A note explains directly in the tool the difference between decimal GB and binary GiB.
Frequently asked questions
Why does my operating system show less storage than the box says?
Manufacturers usually state capacity decimally in GB, while operating systems often display it in binary as GiB — the same capacity looks smaller as “GiB”.
Are my inputs uploaded?
No. Conversion runs entirely locally in the browser.
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