What is the difference between binary and decimal?

Binary (KiB, MiB) uses base 1024: 1 KiB = 1024 bytes. Decimal (KB, MB) uses base 1000: 1 KB = 1000 bytes. RAM and SSDs use binary; hard drive manufacturers traditionally use decimal.

Why does my 1 TB hard drive show as 931 GB?

Hard drives use decimal (1000-based) capacity labeling, while Windows often displays sizes in binary (1024-based). 1,000,000,000,000 bytes ÷ 1,073,741,824 bytes/GiB ≈ 931 GiB.

Which mode should I use?

Use binary for RAM, SSDs, and USB drives. Use decimal for comparing manufacturer specifications of hard drives and external storage.

What are the exact conversion factors?

Binary: 1 KB=1024 B, 1 MB=1024² B, 1 GB=1024³ B. Decimal: 1 KB=1000 B, 1 MB=1000² B, 1 GB=1000³ B.

Data Storage Converter

Free data storage converter supporting binary (KiB, MiB, GiB) and decimal (KB, MB, GB) conversions between bytes, kilobytes, megabytes, gigabytes, terabytes, and petabytes.

Convert between data storage units with binary (1024) or decimal (1000) mode.

Result = Value \times \frac{Factor _{f r o m}}{Factor _{t o}}

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