Productive ToolboxFile Size Converter
Convert file sizes instantly between Bytes, KB, MB, GB, TB, and PB using binary (1024) or decimal (1000) standards.
File Size Converter
Convert between Bytes, KB, MB, GB, TB, and PB using binary (1024) or decimal (1000) standards. All calculations run locally in your browser.
Conversion Settings
1 KB = 1,024 Bytes — used by OS and filesystems
Press Esc to reset
Conversion Summary
Quick Presets
All Conversions
💡 Binary vs Decimal — What's the difference?
Binary (1024-based)
Used by operating systems (Windows, macOS, Linux). 1 KB = 1,024 Bytes. Also called kibibyte (KiB).
Decimal (1000-based)
Used by storage manufacturers and cloud providers. 1 KB = 1,000 Bytes. A 1 TB hard drive is ~931 GiB.
How to Use the File Size Converter
Quick Start
- 1Enter a file size — Type any number into the file size field. Supports decimals and very large values.
- 2Select the source unit — Choose Bytes, KB, MB, GB, TB, or PB from the dropdown.
- 3Choose a standard — Select Binary (1024) for OS/filesystem conversions, or Decimal (1000) for storage hardware.
- 4Get instant results — All units update in real time. Copy individual values or export the full result.
Key Features
- ✓ Instant real-time conversion while typing
- ✓ Binary (1024) and Decimal (1000) standards
- ✓ Covers Bytes, KB, MB, GB, TB, and PB
- ✓ Copy individual unit values to clipboard
- ✓ Export full results as TXT or CSV
- ✓ Share-ready formatted output string
- ✓ Conversion history saved locally
- ✓ 100% browser-based — no data leaves your device
Storage Unit Reference
Byte (B)
Smallest addressable unit
Kilobyte (KB / KiB)
Text files, small documents
Megabyte (MB / MiB)
Images, audio tracks
Gigabyte (GB / GiB)
Apps, HD videos
Terabyte (TB / TiB)
Hard drives, backups
Petabyte (PB / PiB)
Data centers, cloud storage
Frequently Asked Questions
Why does my 1 TB hard drive show 931 GB on Windows?
Hard drive manufacturers use decimal units (1 TB = 1,000,000,000,000 bytes). Windows uses binary units (1 GiB = 1,073,741,824 bytes). So 1,000,000,000,000 ÷ 1,073,741,824 ≈ 931 GiB, which Windows displays as 931 GB.
What is the difference between MB and MiB?
MB (Megabyte) in decimal standard = 1,000,000 bytes. MiB (Mebibyte) in binary standard = 1,048,576 bytes. The IEC introduced the binary prefixes (KiB, MiB, GiB) to eliminate the ambiguity, but both terms are used interchangeably in everyday usage.
Which standard should I use?
Use Binary (1024) when working with operating systems, file systems, RAM, or programming. Use Decimal (1000) when dealing with hard drive specs, SSD marketing, or internet/cloud storage providers.
Can this tool handle very large file sizes like PB?
Yes. The tool uses JavaScript's floating-point arithmetic which handles up to approximately 10^308. Petabyte values and beyond are supported with full precision display.
Is my data sent anywhere when I use this tool?
No. All conversions happen entirely in your browser using JavaScript. No data is sent to any server, logged, or stored externally. Conversion history is saved only in your browser's localStorage.
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