Pick any base between 3 and 36. Digits beyond 9 use letters a–z.
About Number Base Converter
Number Base Converter converts integers between binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16), plus custom base 3–36 conversion for any arbitrary positional system. Enter a value in any base and all representations update instantly. An endianness toggle swaps the byte-order of the hex representation between big-endian (the default, how hex is usually written) and little-endian (how many CPUs store multi-byte integers in memory). Includes a step-by-step conversion breakdown useful for learning and teaching positional numeral systems.
How it Works
1Enter a number in the input field and select its current base.
2All other base representations update immediately.
3For hexadecimal input, use digits 0–9 and letters A–F (case-insensitive).
4For arbitrary bases (e.g. base 32), letters beyond F represent digits 10+.
5Use the custom base field (3–36) to convert to or from any positional system, such as base 12 or base 36.
6Flip the endianness toggle to display the hex value in little-endian byte order (e.g. 0x12345678 → 0x78563412).
Frequently Asked Questions
When do developers use hexadecimal?
Hexadecimal (base 16) is ubiquitous in computing because it maps cleanly to binary: one hex digit represents exactly 4 bits (a nibble). Common uses: colour values in CSS (#FF5733), memory addresses in debuggers (0x7fff0000), byte-level data in networking and cryptography, and character codes in Unicode (U+1F600).
How do I convert a hex colour to RGB values?
Split the 6-character hex into three 2-character pairs: #FF5733 → FF (red), 57 (green), 33 (blue). Convert each pair from hex to decimal: FF=255, 57=87, 33=51. Result: rgb(255, 87, 51). Paste each 2-digit pair into the hex input of this tool to convert it.
What is the difference between binary and hexadecimal notation?
Both represent the same numerical values but with different bases. Binary (base 2) uses only 0 and 1 — every bit is explicitly shown, making it verbose for large numbers. Hexadecimal (base 16) is a compact notation where each digit represents 4 bits, making it 4× shorter than binary. Programmers switch between them constantly when working with bit manipulation.
Can the converter handle negative numbers?
The converter handles non-negative integers. For negative values in binary, the standard representation is two's complement — enter the absolute value, then interpret the MSB (most significant bit) as the sign bit for your specific word width. Two's complement conversion is not automatic in base converters.
What is endianness and when does it matter?
Endianness is the order in which the bytes of a multi-byte value are stored or transmitted. Big-endian stores the most-significant byte first (how humans write numbers and how network protocols typically send them), while little-endian stores the least-significant byte first (how x86 and ARM CPUs keep integers in memory). It matters whenever you inspect raw memory, parse a binary file format, debug a hex dump, or move data between systems with different conventions — the numerical value is the same, but the byte sequence is reversed. Example: the 32-bit value 0x12345678 is stored as the bytes 12 34 56 78 in big-endian and 78 56 34 12 in little-endian.