File Size Converter
Convert bytes across decimal (KB, MB) and binary (KiB, MiB) units with clear labels. Fully client-side — no account, uploads, or remote storage.
Added Apr 18, 2026 · Updated May 1, 2026
Input
Result
Enter a value for value to see your result.
How it works
Converts file sizes between decimal units (KB, MB, GB, TB) and binary units (KiB, MiB, GiB, TiB). Decimal uses powers of 1000; binary uses powers of 1024.
Step by step
- 01Enter the file size value and select the source unit.
- 02Select the target unit to convert to.
- 03Decimal units (KB/MB/GB/TB) use powers of 1000.
- 04Binary units (KiB/MiB/GiB/TiB) use powers of 1024.
Examples
1 GB to MB
1 GB = 1000 MB (decimal: 1 × 1000^3 ÷ 1000^2).
Inputs
- Value:
- 1
- From:
- gb
- To:
- mb
Result
- Result:
- 1,000 MB
- In Bytes:
- 1,000,000,000 B
1 GiB to MiB
1 GiB = 1024 MiB (binary: 1 × 1024^3 ÷ 1024^2).
Inputs
- Value:
- 1
- From:
- gib
- To:
- mib
Result
- Result:
- 1,024 MiB
- In Bytes:
- 1,073,741,824 B
Frequently asked questions
What is the difference between MB and MiB?
MB (megabyte) uses the decimal system: 1 MB = 1,000,000 bytes. MiB (mebibyte) uses binary: 1 MiB = 1,048,576 bytes. Operating systems often report sizes in MiB but label them as MB.
How many MB is 1 GB?
1 GB = 1,000 MB in decimal (SI). However, 1 GiB = 1,024 MiB in binary (IEC). Hard drive manufacturers use decimal; OS storage reports often use binary.
Why does my 1 TB SSD show less than 1 TB in Windows?
Marketing capacity is decimal terabytes (1e12 bytes) while some OS views use binary tebibytes (1024^4). The difference is labeling, not missing chips — firmware and over-provisioning also reserve space.
Which unit should I use in bandwidth vs file size?
Network speeds are usually decimal bits per second (Mb/s). File sizes are bytes. When estimating download time, convert bits to bytes (÷8) and watch whether the speed label is Mb or MB.
Does this tool know how a specific cloud bills storage?
No. Vendors may bill on compressed, deduplicated, or minimum object sizes. Use this converter for human-readable estimates, then confirm billing rules in your provider's docs.