Free Data Size Converter that works offline
Convert storage and transfer sizes while keeping decimal and binary unit names explicit. This avoids the common mistake of treating megabytes and mebibytes as identical.
What this data size converter does
SI units such as MB use powers of 1,000, while IEC units such as MiB use powers of 1,024. Both are valid but produce different numbers for the same byte count, especially at gigabyte and terabyte scales.
How to use the Data Size Converter
- Enter or paste a numeric data size and source and target units into the tool.
- Adjust the available options so they match the format and result you need.
- Choose Convert and review the equivalent decimal or binary byte-unit value before using it.
- Copy or download the result, then clear the page if the input was sensitive.
Common uses
- Comparing disk and operating-system size reports
- Converting upload limits
- Estimating transfer and cache sizes
- Teaching decimal versus binary prefixes
Private processing and offline access
This tool does not submit your input to a conversion server. Processing takes place inside the browser using local JavaScript and standard Web APIs. After the PWA has been installed or cached, the page and its core features remain available without an internet connection. Closing or clearing the page removes unsaved input; the tool does not create an account or cloud history.
Tips for accurate results
- Check whether a product label uses decimal units.
- Network speeds are often in bits, not bytes.
- The result does not include filesystem or protocol overhead.
Frequently asked questions
Does this tool upload my data?
No. Data Size Converter processes its input in the current browser and does not submit it to a conversion API.
What input does the Data Size Converter accept?
Bytes and decimal powers of 1,000 through TB, plus binary powers of 1,024 through TiB, are included.
Can I use this tool offline?
Yes. Once the Offline Tools PWA has cached the page, the core feature works without an internet connection.