Free Data Storage Converter
Convert data storage units instantly — bits, bytes, kilobytes, megabytes, gigabytes, terabytes, and petabytes. Free, symmetrical, no sign-up.
Exact Conversion Formula & Multipliers
Digital storage has two competing conventions this converter distinguishes explicitly: decimal (SI) prefixes where 1 kilobyte = 1,000 bytes, and binary (IEC) prefixes where 1 kibibyte = 1,024 bytes, since computers address memory in powers of two. Storage manufacturers typically advertise in decimal units while operating systems often report binary units, which is the well-known reason a '1 TB' drive shows less than 1,000 GB of usable space in Windows or macOS.
Practical Real-World Scenarios
- Buying storage devices: a drive marketed as '1 TB' (1,000,000,000,000 bytes decimal) shows as roughly 931 GiB in an operating system using binary units — not a manufacturing shortfall, but a unit mismatch.
- Network and internet speeds: internet service providers advertise speed in megabits per second (Mbps), while file sizes are shown in megabytes (MB) — an 8x difference that confuses download time estimates.
- Software development and IT: RAM and cache sizes are conventionally binary (1,024-based), while network transfer and disk marketing figures are conventionally decimal, requiring developers to track which convention applies where.
Historical & Technical Background
The kilobyte's ambiguity dates to early computing, when engineers reused the metric 'kilo' prefix loosely to mean 1,024 (2¹⁰) because it was close enough to 1,000 for casual use and matched binary addressing. As storage devices grew into gigabytes and terabytes, the compounding gap between 1,000-based and 1,024-based counting became large enough to matter commercially, prompting the International Electrotechnical Commission to introduce distinct binary prefixes (kibi-, mebi-, gibi-) in 1998 — though informal usage of 'KB' for either meaning persists today.
Precision & Accuracy Statement
Every conversion factor used on this page is checked against internationally recognized reference standards — IEC 80000-13 binary-prefix standards and the International System of Units decimal-prefix conventions — rather than approximated or rounded for display. Where a constant is fixed by international definition (such as 1 inch = 2.54 cm, or standard gravity = 9.80665 m/s²), we use the exact defined value. Where a figure is a practical industry convention rather than a physical constant, that distinction is stated explicitly above so results are never presented with false precision.
How This Converter Works
Data storage uses powers of 1,000 (SI decimal) for storage marketing — where 1 KB = 1,000 bytes — but operating systems often use binary prefixes where 1 KiB = 1,024 bytes. Our converter uses the standard SI decimal system.
Common Conversions
| Unit | Bytes | Common Use |
|---|---|---|
| 1 Byte (B) | 1 byte | Single character of text |
| 1 Kilobyte (KB) | 1,000 bytes | Short email or text document |
| 1 Megabyte (MB) | 1,000,000 bytes | 1–2 minute MP3 audio file |
| 1 Gigabyte (GB) | 1,000,000,000 bytes | ~250 photos or ~4 minutes of 4K video |
| 1 Terabyte (TB) | 1,000,000,000,000 bytes | External hard drive capacity |
| 1 Petabyte (PB) | 1,000,000,000,000,000 bytes | Large data centre storage |