Convert between digital storage units instantly. All values shown at once.
There are two standards for digital storage:
| Decimal (Base-10) | Binary (Base-2) |
|---|---|
| 1 KB = 1,000 B | 1 KiB = 1,024 B |
| 1 MB = 1,000 KB | 1 MiB = 1,024 KiB |
| 1 GB = 1,000 MB | 1 GiB = 1,024 MiB |
| 1 TB = 1,000 GB | 1 TiB = 1,024 GiB |
Hard drive manufacturers use base-10. Operating systems typically use base-2. This is why a "500 GB" drive shows as ~465 GiB in Windows.
Digital storage is measured in units derived from the byte. A byte consists of 8 bits, and each bit is a binary digit — either a 0 or a 1. As data storage needs grew, larger units were introduced. Today we commonly use kilobytes, megabytes, gigabytes, and terabytes to describe everything from file sizes to hard drive capacities.
The confusion between base-10 (decimal) and base-2 (binary) units has existed since the early days of computing. Hard drive manufacturers measure storage in powers of 10 (1 KB = 1,000 bytes) because it makes their products appear larger. Operating systems like Windows measure in powers of 2 (1 KiB = 1,024 bytes) because computers are binary. The IEC introduced the kibibyte, mebibyte, and gibibyte prefixes in 1998 to eliminate this ambiguity.
Hard drives are sold using base-10 measurements, but your operating system displays space in base-2. A 1 TB drive contains 1,000,000,000,000 bytes, which is only about 931 GiB (gibibytes) when measured in binary. This is not missing storage — it is a difference in measurement standards.
A bit is the smallest unit of digital data and can be either 0 or 1. A byte consists of 8 bits. Internet speeds are usually measured in bits per second (Mbps), while file sizes are measured in bytes (MB). This is why a 100 Mbps connection downloads a 100 MB file in about 8 seconds.
One petabyte equals 1,000 terabytes or about 1 quadrillion bytes. To put it in perspective, 1 petabyte could store approximately 500 billion pages of text, or about 13.3 years of HD video.