File Size / Data Unit Converter
Convert file sizes between bytes, kilobytes, megabytes, gigabytes, and more.
The File Size Converter handles both SI units (KB, MB, GB, TB, PB where 1 KB = 1,000 bytes) and binary units (KiB, MiB, GiB, TiB where 1 KiB = 1,024 bytes). This distinction is important when working with storage hardware, operating systems, and network speeds that may report sizes differently.
Frequently Asked Questions
What is the difference between KB and KiB? +
KB (Kilobyte) is an SI unit equal to 1,000 bytes, while KiB (Kibibyte) is a binary unit equal to 1,024 bytes. Hard drive manufacturers use SI units; operating systems often use binary units — which is why a "1 TB" drive appears smaller in Windows.
Why do very small values show scientific notation? +
When a converted value is smaller than 1 (e.g. 1 byte expressed in GB), the number is so small that scientific notation is more readable than showing many leading zeros after the decimal point.
Can I enter decimal values? +
Yes — decimal values like 1.5 GB or 2.75 MiB are fully supported. The converter calculates the exact byte count and derives all other units from that.
Frequently Asked Questions
- 1 MB (IEC binary) = 1,048,576 bytes = 1024 KB. 1 MB (SI decimal) = 1,000,000 bytes. Operating systems typically use binary (IEC) but sometimes label it as MB.