About

System administrators and developers often face a discrepancy between advertised storage capacity and the actual space available in an operating system. This occurs because hardware manufacturers adhere to decimal SI standards where 1 KB equals 1000 Bytes. Conversely, operating systems like Windows utilize binary IEC standards where 1 KiB equals 1024 Bytes.

Accurate conversion is essential for server partitioning and cloud resource allocation. Misinterpreting these values leads to provisioning errors or unexpected costs in large-scale data migrations. This tool provides precise bidirectional conversions. It simultaneously calculates Metric and IEC values to ensure clarity across different technical contexts (e.g., purchasing hardware vs. configuring file systems).

Formulas

The core distinction lies in the base of the multiplier. The International System of Units (SI) uses base 10.

Size_SI = n × 1000^k

The International Electrotechnical Commission (IEC) defines binary prefixes using base 2.

Size_IEC = n × 1024^k

To convert from a decimal Gigabyte (GB) to a binary Gibibyte (GiB), the ratio is applied.

Val_GiB = Val_GB × 10⁹2³⁰ ≈ Val_GB × 0.931

Reference Data

Unit Name	Symbol (SI)	Symbol (IEC)	Value (Bytes SI)	Value (Bytes IEC)	Typical Use Case
Byte	B	B	1	1	ASCII Character
Kilobyte	KB	KiB	10³	2¹⁰	Text Files
Megabyte	MB	MiB	10⁶	2²⁰	Images, MP3s
Gigabyte	GB	GiB	10⁹	2³⁰	Movies, SSDs
Terabyte	TB	TiB	10¹²	2⁴⁰	HDD, Cloud Storage
Petabyte	PB	PiB	10¹⁵	2⁵⁰	Data Centers
Exabyte	EB	EiB	10¹⁸	2⁶⁰	Global Internet Traffic
Zettabyte	ZB	ZiB	10²¹	2⁷⁰	Big Data Total

Frequently Asked Questions

This is a naming convention conflict. The hard drive manufacturer defines 1 TB as 1,000,000,000,000 bytes (Base 10). Windows calculates capacity using binary prefixes (Base 2) where 1 TiB equals 1,099,511,627,776 bytes. When you divide the manufacturer's byte count by the Windows binary divisor, you get approximately 931 GiB.

Use MiB (Mebibyte) when referring to precise RAM capacity, operating system file sizes, or cache sizes, as these are inherently binary. Use MB (Megabyte) for network bandwidth (Mbps), hard drive packaging, or DVD/Blu-ray capacities where decimal units are the industry standard.

Yes. A Byte consists of 8 bits. Network speeds are often measured in bits (Gbps), while storage is measured in Bytes (GB). This tool accounts for the factor of 8 when converting between these data types.

Javascript uses double-precision floating-point format. This provides accuracy up to 15 significant digits. For extremely large values (Exabytes and above), minor rounding differences may occur at the byte level, but the values remain accurate for all practical storage planning purposes.