Data Storage Converter – Binary & Decimal

Bit bit
Byte B
Kilobyte KB
Megabyte MB
Terabyte TB
Petabyte PB

Data Storage Units Explained

Digital storage is measured in bits and bytes. There are two competing standards: binary (IEC), which uses powers of 1024, and decimal (SI), which uses powers of 1000. This difference explains why a "1 TB" hard drive shows less storage in your operating system — OS reports in binary, manufacturers advertise in decimal.

Binary vs Decimal Storage

UnitBinary (1024)Decimal (1000)
Kilobyte (KB)1,024 Bytes1,000 Bytes
Megabyte (MB)1,024 KB = 1,048,576 B1,000 KB = 1,000,000 B
Gigabyte (GB)1,024 MB1,000 MB
Terabyte (TB)1,024 GB1,000 GB
Petabyte (PB)1,024 TB1,000 TB

Frequently Asked Questions

How many MB are in 1 GB?

In binary (IEC standard), 1 GB = 1024 MB. In decimal (SI standard), 1 GB = 1000 MB. Hard drive manufacturers use the decimal standard, which is why a '1 TB' drive shows as ~931 GB on your computer.

What is the difference between binary and decimal storage units?

Binary uses powers of 1024 (1 KB = 1024 B), defined by IEC as kibibyte (KiB). Decimal uses powers of 1000 (1 KB = 1000 B), used by storage manufacturers. Operating systems typically use binary, causing the apparent discrepancy in drive capacities.

How many GB is 1 TB?

In binary: 1 TB = 1024 GB. In decimal: 1 TB = 1000 GB. A 1 TB hard drive from a manufacturer may show only about 931 GB in Windows, which uses binary calculation.

How many bits are in 1 byte?

There are exactly 8 bits in 1 byte. This is universally consistent in both binary and decimal standards.

What is a Petabyte?

A Petabyte (PB) is 1024 TB (binary) or 1000 TB (decimal). It is used to describe very large data stores — cloud providers and data centres operate at petabyte scale.

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