About

Data storage and transmission rely on precise unit conversions. A single bit (b) represents a binary digit, while a byte (B) equals 8 bits. Confusion arises when mixing SI decimal prefixes (kilo = 10³) with IEC binary prefixes (kibi = 2¹⁰). A file labeled 1 GB by your operating system may actually be 1 GiB (1,073,741,824 bytes), not 1,000,000,000 bytes. This discrepancy causes storage calculations to fail by up to 7.4% at the gigabyte scale.

Network bandwidth compounds the problem: ISPs advertise speeds in bits per second (Mbps), while downloads display in bytes per second (MB/s). A 100 Mbps connection delivers approximately 12.5 MB/s maximum throughput. This converter handles all standard units from bits through exabytes, distinguishing SI and IEC standards per ISO/IEC 80000-13.

Formulas

Conversion between any two data units uses bits as the canonical base. The input value is first converted to bits, then from bits to the target unit.

V_output = V_input × F_inputF_output

Where V_input is the numeric value entered, F_input is the conversion factor of the source unit (bits per unit), and F_output is the conversion factor of the target unit.

Bits per Byte: 1 B = 8 b

SI Prefix (Decimal): 1 kB = 1000 B = 10³ B

IEC Prefix (Binary): 1 KiB = 1024 B = 2¹⁰ B

The percentage difference between SI and IEC units grows with scale: 2.4% at kilo, 4.9% at mega, 7.4% at giga, 10.0% at tera.

Reference Data

Unit	Symbol	Standard	Bits	Bytes
Bit	b	Base	1	0.125
Nibble	nibble	Base	4	0.5
Byte	B	Base	8	1
Kilobit	kb	SI (Decimal)	1,000	125
Kibibit	Kib	IEC (Binary)	1,024	128
Kilobyte	kB	SI (Decimal)	8,000	1,000
Kibibyte	KiB	IEC (Binary)	8,192	1,024
Megabit	Mb	SI (Decimal)	1,000,000	125,000
Mebibit	Mib	IEC (Binary)	1,048,576	131,072
Megabyte	MB	SI (Decimal)	8,000,000	1,000,000
Mebibyte	MiB	IEC (Binary)	8,388,608	1,048,576
Gigabit	Gb	SI (Decimal)	1,000,000,000	125,000,000
Gibibit	Gib	IEC (Binary)	1,073,741,824	134,217,728
Gigabyte	GB	SI (Decimal)	8,000,000,000	1,000,000,000
Gibibyte	GiB	IEC (Binary)	8,589,934,592	1,073,741,824
Terabit	Tb	SI (Decimal)	10¹²	125 × 10⁹
Tebibit	Tib	IEC (Binary)	2⁴⁰	2³⁷
Terabyte	TB	SI (Decimal)	8 × 10¹²	10¹²
Tebibyte	TiB	IEC (Binary)	8 × 2⁴⁰	2⁴⁰
Petabit	Pb	SI (Decimal)	10¹⁵	125 × 10¹²
Pebibit	Pib	IEC (Binary)	2⁵⁰	2⁴⁷
Petabyte	PB	SI (Decimal)	8 × 10¹⁵	10¹⁵
Pebibyte	PiB	IEC (Binary)	8 × 2⁵⁰	2⁵⁰
Exabit	Eb	SI (Decimal)	10¹⁸	125 × 10¹⁵
Exbibit	Eib	IEC (Binary)	2⁶⁰	2⁵⁷
Exabyte	EB	SI (Decimal)	8 × 10¹⁸	10¹⁸
Exbibyte	EiB	IEC (Binary)	8 × 2⁶⁰	2⁶⁰

Frequently Asked Questions

Hard drive manufacturers use SI units (1 TB = 1,000,000,000,000 bytes), while Windows reports capacity in binary units labeled as GB (actually GiB = 1,073,741,824 bytes). Dividing 1,000,000,000,000 by 1,073,741,824 yields approximately 931 GiB. This 7.4% discrepancy is not missing space but a unit mismatch.

Lowercase "b" denotes bits, uppercase "B" denotes bytes. 1 MB (megabyte) = 8 Mb (megabits). Internet speeds are typically advertised in Mbps (megabits per second), while file sizes display in MB (megabytes). A 100 Mbps connection transfers at most 12.5 MB per second under ideal conditions.

Use IEC units when precision matters for computing: RAM specifications, disk partitions, file system calculations, and programming contexts where powers of 2 are native. RAM is always manufactured in binary increments (e.g., 16 GiB = 17,179,869,184 bytes). SI units are appropriate for network bandwidth, storage marketing, and human-readable approximations.

A nibble equals 4 bits, representing half a byte. It can encode a single hexadecimal digit (0-F, values 0-15). Nibbles are relevant in low-level programming, memory addressing, and encoding schemes like Base16.

Yes. Enter decimal values such as 1.5 GB or 0.25 TB. Results display up to 15 significant digits for precision, with trailing zeros removed. For extremely small or large results, scientific notation may provide better readability when copying values.

Historical convention: telecommunications transmitted serial data one bit at a time, making bits the natural unit. Computing adopted bytes (8 bits) as the minimum addressable memory unit because early character encodings required 8 bits. This divergence persists in industry standards and marketing.