A complete data storage converter that moves a value up and down the whole ladder — bit, byte, KB, MB, GB, TB and PB — in either counting convention. It is built for anyone sizing a backup, comparing a hard-drive spec against what their operating system reports, planning cloud storage, or just settling the eternal argument about whether a “gigabyte” means 1,000,000,000 or 1,073,741,824 bytes. Both answers are correct; they simply belong to different systems, and this tool shows you both side by side.
How it works
Pick a counting mode first. Decimal (1000) is the SI convention used by storage vendors, broadband providers and networking gear, where each step multiplies by 1000. Binary (1024) is the IEC convention used by most operating systems and by RAM, where each step multiplies by 1024. One byte is always 8 bits in either mode — the 1000-versus-1024 choice only kicks in from the kilobyte rung upward.
Type an amount, choose its From unit, and read the headline result in your chosen To unit. Below that, a live cross-fill grid lists the same physical size in every single unit at once. Edit any field in that grid and the entire grid re-bases to your new number, so you can drive the conversion from bits, from gigabytes, or from anywhere in between. A swap button flips the From and To units while preserving the size, and a permanent reference table shows exactly how many bytes sit in one of each unit under both systems. Sensible precision keeps the figures readable, switching to scientific notation only for extreme magnitudes.
Worked example
Suppose you buy a drive advertised as 2 TB. Drive makers count in decimal, so that is
2,000,000,000,000 bytes. Set the mode to Decimal (1000), enter 2 with From = TB:
- In bytes: 2,000,000,000,000
- In GB (decimal): 2000
Now flip the mode to Binary (1024) and keep the same 2,000,000,000,000 bytes by typing that figure into the byte field. The grid now reports about 1.819 TB and 1862.6 GB — which is the “1.82 TB / 1863 GB” your operating system would display. Nothing was lost; the drive is simply being measured with 1024-steps instead of 1000-steps.
Conversion reference
| Unit | Decimal (×1000) | Binary (×1024) |
|---|---|---|
| 1 byte | 8 bits | 8 bits |
| 1 KB | 1,000 bytes | 1,024 bytes |
| 1 MB | 1,000,000 bytes | 1,048,576 bytes |
| 1 GB | 1,000,000,000 bytes | 1,073,741,824 bytes |
| 1 TB | 1,000,000,000,000 bytes | 1,099,511,627,776 bytes |
| 1 PB | 1,000,000,000,000,000 bytes | 1,125,899,906,842,624 bytes |
The two columns diverge by about 2.4% per step, so by the terabyte rung the gap is roughly 10% — which is exactly why a 1 TB drive shows as about 0.909 binary TB. Every figure here is calculated locally in your browser; no numbers are uploaded or stored.