Number Base Converter

What is Number Base Converter?

If you work with low-level programming, networking, hardware, or any form of digital systems, you constantly need to convert numbers between bases. What is 0xFF in decimal? What is 192 in binary? What is the octal representation of file permission 755? AllKit's Number Base Converter gives you instant, real-time conversion between binary, octal, decimal, and hexadecimal — all four updating simultaneously as you type in any field.

Unlike other converters that make you select an input base and output base, then press a Convert button, this tool shows all four representations at once. Type a decimal number and immediately see the binary, octal, and hex equivalents. Type a hex value and see the decimal, binary, and octal instantly. There is no button to press, no form to submit — the conversion is truly real-time.

The tool includes quality-of-life features that developers actually need: digit grouping for readability (binary digits grouped in nibbles of 4, hex digits in pairs), optional base prefixes (0b, 0o, 0x) for copy-paste into code, input validation that only allows valid characters for each base, and a quick reference section showing common values like MAX_INT boundaries for 8-bit, 16-bit, 32-bit, and 64-bit integers.

Everything runs locally in your browser with zero dependencies. Whether you are debugging network protocols, setting Unix file permissions, working with color values, analyzing memory addresses, or just doing homework, this is the fastest number base converter you will find. No ads, no signup, no nonsense — just type and convert.

Why use AllKit?

• No ads, no distractions — a clean interface that lets you focus on the task
• Privacy-first — 100% client-side processing, nothing is uploaded
• Free forever — core tools are free with no usage limits
• API available — integrate into your workflow via our REST API

How to Use Number Base Converter

1. Type a number in any of the four input fields: Binary, Octal, Decimal, or Hexadecimal. All other fields update instantly as you type.
2. For binary input, use only 0 and 1. For octal, use digits 0 through 7. For decimal, use digits 0 through 9. For hexadecimal, use digits 0 through 9 and letters A through F (case-insensitive).
3. Toggle the Prefix option to show or hide base prefixes (0b for binary, 0o for octal, 0x for hex) in the output. This is useful when copying values directly into source code.
4. Toggle Digit Grouping to add spaces between digit groups for improved readability. Binary digits are grouped in sets of 4 (nibbles), and hex digits are grouped in pairs (bytes).
5. Click the Copy button next to any field to copy that representation to your clipboard.
6. Use the common values reference at the bottom to quickly look up important boundaries like the maximum values for 8-bit (255), 16-bit (65535), and 32-bit (4294967295) integers.
7. To clear all fields and start over, delete the content from any input field or use the Clear button.

Common Use Cases

Technical Details

Conversion uses JavaScript's built-in parseInt() for input parsing and toString() for output formatting, both of which handle arbitrary-precision integers up to Number.MAX_SAFE_INTEGER (2^53 - 1 = 9007199254740991). For most practical use cases, this range is more than sufficient.

Input validation is applied per field in real-time. Binary fields only accept 0 and 1. Octal fields accept 0-7. Decimal fields accept 0-9. Hexadecimal fields accept 0-9 and A-F (case-insensitive). Invalid characters are silently rejected.

Digit grouping uses space separators for universal readability. Binary digits are grouped in nibbles (groups of 4), matching how hardware engineers and protocol specifications typically display binary values. Hex digits are grouped in pairs (bytes), matching the standard representation for memory dumps, MAC addresses, and byte sequences.

The tool handles leading zeros correctly — entering '007' in octal is interpreted as 7, not as an error. Base prefixes (0b, 0o, 0x) in the output are purely visual and match the conventions used in JavaScript, Python, C, and most modern programming languages.