Free Online Hex, Binary, Decimal & Octal Base Converter
Arbitrary precision matrix conversion, custom bases formats, IEEE 754 floats, and 64-bit Two's Complement matrices.
Synchronized Matrix Input
Typing in any field instantly updates the rest.
About the Number Base Converter
Programmers constantly work across number bases — binary in bitwise operations, hex in memory addresses and color values, octal in Unix permissions. Converting between them mentally is error-prone. This tool converts between binary, octal, decimal, hexadecimal, and any custom base from 2 to 36, with two's complement support for signed integers.
Common use cases
Hex ↔ Decimal
Convert memory addresses, color values, and byte sequences between hex and decimal for debugging and documentation.
Binary Bitwise
Visualize bitmasks, flags, and bitwise operations in binary. See exactly which bits are set in a permission mask or status register.
Octal Permissions
Convert Unix chmod octal values (755, 644) to binary to understand exactly which permission bits are set for owner, group, and others.
Two's Complement
Convert signed integers to their two's complement binary representation — essential for understanding how CPUs represent negative numbers.
Pipeline
- Chmod Calculator — convert octal permission values to symbolic notation.
- Color Converter — convert hex color values to RGB and other formats.
Frequently asked
- Is my data sent to a server?
- No. All conversions run 100% in your browser. No numbers or values are transmitted anywhere.
- What is the difference between binary, octal, decimal, and hexadecimal?
- Binary (base 2) uses digits 0-1 — the native language of computers. Octal (base 8) uses 0-7 — common in Unix permissions. Decimal (base 10) uses 0-9 — the human standard. Hexadecimal (base 16) uses 0-9 and A-F — widely used in memory addresses, colors, and encoding.
- What is two's complement?
- Two's complement is the standard way computers represent negative integers in binary. To negate a number: flip all bits, then add 1. For example, -1 in 8-bit two's complement is 11111111 (255 unsigned). This representation makes arithmetic circuits simpler.
- Why is hexadecimal used in programming?
- Each hex digit represents exactly 4 binary bits, making hex a compact human-readable representation of binary data. Memory addresses, color values (#FF5733), byte values, and bitmasks are all naturally expressed in hex.
- What is a custom base conversion?
- Any integer base from 2 to 36 is supported. Base 36 uses digits 0-9 and letters A-Z, producing compact representations of large numbers — used in URL shorteners and ID generation.