Digital Storage calculator
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Digital storage is measured in bytes (B), where 1 byte equals 8 bits. Larger units use either decimal prefixes (1 KB = 1,000 B; 1 MB = 10⁶ B; 1 GB = 10⁹ B) or binary IEC prefixes (1 KiB = 1,024 B; 1 MiB = 2²⁰ B; 1 GiB = 2³⁰ B). A 1 TB drive in decimal labeling stores 1,000,000,000,000 bytes, which the operating system may display as ~931 GiB.
Open the live digital storage converter for any input value.
Two parallel prefix systems exist for digital storage. The decimal SI prefixes (kilo, mega, giga, tera) work in powers of 10: 1 KB = 1,000 bytes, 1 MB = 1,000,000 bytes. The IEC binary prefixes (kibi, mebi, gibi, tebi) work in powers of 2: 1 KiB = 1,024 bytes, 1 MiB = 1,048,576 bytes, 1 GiB = 1,073,741,824 bytes. The two systems differ by about 2.4% at the kilo scale and grow apart at each higher prefix.
Disk and SSD manufacturers use decimal prefixes (a '1 TB' drive holds 10¹² bytes). RAM manufacturers and most operating systems use binary prefixes (Windows reports a 1 TB drive as 931 GiB, though it labels the unit 'GB'). The mismatch is the source of the persistent 'my drive is smaller than advertised' complaint.
A high-resolution photo is 5-20 MB. A standard-definition movie is 1-2 GB; HD is 4-8 GB; 4K HDR is 30-60 GB. A typical SSD on a 2026 consumer laptop holds 512 GB to 2 TB. A movie at full streaming bitrate (~25 Mbps for 4K) uses about 11 GB per hour.
At the larger scale: a hyperscale data center cluster stores petabytes (PB = 10¹⁵ B) to exabytes (EB = 10¹⁸ B). The global digital storage capacity in 2026 is estimated in the hundreds of zettabytes (ZB = 10²¹ B).
For casual comparisons, treating KB / KiB as roughly the same is fine. For precise capacity calculations (disk-image sizes, backup planning, RAID arithmetic), use the correct prefix. The IEC introduced kibi/mebi/gibi/tebi in 1998 specifically to remove the ambiguity, and Linux, macOS, and some technical Windows surfaces have adopted them; consumer Windows still uses 'KB' / 'MB' / 'GB' for binary multiples in most places.
Bits vs bytes is a separate confusion. Network speeds use bits (Mbps = megabits per second); file sizes use bytes (MB). 1 byte is 8 bits, so a 100 Mbps connection delivers about 12.5 MB/s in ideal conditions, not 100 MB/s.
| From | Equivalent |
|---|---|
| 1 byte (B) | 8 bits |
| 1 KB (decimal) | 1,000 bytes |
| 1 KiB (binary) | 1,024 bytes |
| 1 MB (decimal) | 10⁶ bytes |
| 1 MiB (binary) | 1,048,576 bytes |
| 1 GB (decimal) | 10⁹ bytes |
| 1 GiB (binary) | 1,073,741,824 bytes |
| 1 TB (decimal) | 10¹² bytes, 0.909 TiB |
| 1 TiB (binary) | 1,099,511,627,776 bytes, 1.1 TB |
| 1 PB (decimal) | 10¹⁵ bytes |
Disk manufacturers use decimal TB (10¹² bytes). Windows reports drive capacity using binary GiB (2³⁰ bytes per 'GB') but labels it 'GB'. 10¹² bytes ÷ 2³⁰ bytes/GiB ≈ 931 GiB. Nothing is missing; the two units are labeled the same but have different sizes.
MB is the decimal megabyte (1,000,000 bytes). MiB is the binary mebibyte (1,048,576 bytes). They differ by about 4.9%. The IEC introduced MiB in 1998 to make the distinction explicit.
Decimal: 1 GB = 10⁹ bytes = 1,000,000,000 bytes. Binary: 1 GiB = 2³⁰ bytes = 1,073,741,824 bytes. Context determines which one a given source means.
No. 1 byte equals 8 bits. Network speeds are usually quoted in bits per second (Mbps); file sizes are quoted in bytes (MB). A 100 Mbps connection delivers about 12.5 MB/s of file throughput.
Petabyte (PB, 10¹⁵ B), exabyte (EB, 10¹⁸ B), zettabyte (ZB, 10²¹ B), yottabyte (YB, 10²⁴ B). The binary equivalents are PiB, EiB, ZiB, YiB.