Data Size Converter

Data Size Conversion uses bytes as the base unit. This converter uses decimal (SI) prefixes where each step is 1,000×.

Key relationships:

• 1 KB = 1,000 bytes
• 1 MB = 1,000 KB = 1,000,000 bytes
• 1 GB = 1,000 MB = 1,000,000,000 bytes
• 1 TB = 1,000 GB = 1,000,000,000,000 bytes
• 1 PB = 1,000 TB = 1,000,000,000,000,000 bytes

Decimal vs. Binary: Storage manufacturers use decimal (1 KB = 1,000 bytes), while operating systems often use binary (1 KiB = 1,024 bytes). This is why a “500 GB” drive shows as ~465 GB in your OS.

Common references:

• A text email: ~5 KB
• An MP3 song: ~5 MB
• A full-length movie (HD): ~4 GB
• A modern video game: ~50–100 GB

That decimal-versus-binary gap is worth understanding, because it explains a complaint everyone has had. A “1 TB” drive is sold as a trillion bytes (decimal), but Windows reports capacity in binary units while still labeling them “GB,” so the same drive shows up as about 931. Nothing is missing; the two sides are just counting with different-sized units, and the technically correct binary label would be 931 GiB. Don’t confuse data size with bandwidth, either: storage is counted in bytes, while internet speed is counted in bits, which are eight times smaller. The “i” in KiB and GiB was invented to end this confusion, though storage marketing and operating systems never fully adopted it.