Data Size Converter

How to use

1. 1Type a value into the input. You can paste a number with a comma decimal, a thousand separator, or an optional unit suffix like 1.5 GB or 1024MiB.
2. 2Pick the source unit from the SI (decimal) or IEC (binary) groups. The two result columns update with every other unit at once.
3. 3Use Show units to focus on SI only, IEC only, or both, and Decimal places to round results between 0 and 6 places.
4. 4Read the Human readable card to see the cleanest representation of your value in each system, the same way an operating system or storage dashboard would label it.
5. 5Tap a common reference point (CD-ROM, DVD, 4K movie, SSD, hard drive) to load that size, or click Copy on any result card to grab the converted value.

About this tool

Data Size Converter turns any byte count or storage size into every common unit at the same time, so you can read SI (decimal) and IEC (binary) values side by side instead of guessing which one a tool, drive label, or operating system is using. Type a number, pick a source unit (Bytes, KB, MB, GB, TB, PB or KiB, MiB, GiB, TiB, PiB), and the result cards update instantly with the converted value, the byte count, and a copy button on every result. Conversions go through a single canonical bytes value internally so SI and IEC stay consistent: 1024 MB equals 1.024 GB, 1024 MiB equals 1.024 GiB, and 1 GiB equals 1.073741824 GB. Inputs accept comma decimal separators, thousand separators, an optional unit suffix (KB, MiB, GB, etc), and even scientific notation, so values pasted from a script, a spreadsheet, or a vendor spec sheet just work. When the suffix you typed does not match the selected source unit, a one-click swap switches the source so you do not silently get the wrong reading. The tool also surfaces a human-readable summary that picks the most appropriate unit (the largest one where the value is at least 1) for each system, which is exactly what file managers, cloud storage dashboards, and system monitors do when they show 1.5 GB or 932 GiB. The decimal places control rounds results to 0, 2, 4, or 6 places depending on whether you are answering a marketing question or a precise file system reading. A reference panel ships real-world sizes (an SMS, a tweet, an HD photo, a CD-ROM, a DVD, a Blu-ray, a 4K movie, a phone, an SSD, a hard drive) that tap to load instantly. Useful for sanity checking storage labels (a 1 TB drive really does hold a trillion bytes, even when Windows shows 931 GB), planning backups and snapshots, calculating bandwidth budgets, sizing cloud storage tiers, validating download estimates, comparing sizes between Linux ls -lh, macOS Finder, and Windows Explorer, and any moment you need to translate a data size without trusting a fragile mental shortcut. Everything runs locally on your device, so the values you type here are never uploaded.

Free to use. Works in your browser. No signup, no login.