Quick Reference

Binary (Base 1024)

Unit Bytes
1 KB1,024
1 MB1,048,576
1 GB1,073,741,824
1 TB1,099,511,627,776

Decimal (Base 1000)

Unit Bytes
1 KB1,000
1 MB1,000,000
1 GB1,000,000,000
1 TB1,000,000,000,000

Understanding File Size Units

Binary vs Decimal

Computer systems traditionally use binary (base 1024) for memory and storage, while manufacturers often use decimal (base 1000) for marketing. This creates a ~7% difference that grows with larger units.

When to Use Which?

Binary (1024): Operating systems, RAM, file systems
Decimal (1000): Hard drive capacities, network speeds, ISP bandwidth

IEC Standard

The IEC recommends using KiB, MiB, GiB for binary units (1024) and KB, MB, GB for decimal units (1000), though this isn't universally adopted.