Base Converter Free Online
Convert any integer between bases 2–36 instantly. Binary, octal, decimal, hexadecimal, and custom radix — all displayed at once. Includes 4-bit nibble grouping. Runs entirely in your browser.
Converted Values
Pro — batch file conversion, signed / two's complement, API access
API access · Priority queue · Team workspace
How It Works
Enter Your Number
Type any non-negative integer into the input field and choose its source base from the dropdown. You can enter it in binary, octal, decimal, hexadecimal, or any base up to 36.
Instant Conversion
All output bases update in real time as you type — no submit button needed. Results appear for binary, octal, decimal, hex, base-32, base-36, and a 4-bit nibble view simultaneously.
Copy Any Result
Click Copy next to any output to put it on your clipboard. For custom radixes (base-5, base-13, etc.) enter the radix number in the custom base field for an additional result.
Base Converter Features
Instant multi-base conversion with bit-group display and custom radix support
All Common Bases
Binary (2), octal (8), decimal (10), hexadecimal (16), base-32, and base-36 are all shown simultaneously so you never need to convert more than once.
Custom Radix
Need base-5, base-13, or any other radix? Enter any value from 2 to 36 in the custom base field to get an additional converted result for that specific base.
Bit-Group View
The binary output is split into 4-bit nibbles (e.g. 1111 0000) for easier reading of byte values, making it ideal for checking CPU flags, memory addresses, and binary protocols.
Real-Time Output
Every keystroke instantly updates all bases — no submit button, no page reload. The conversion is synchronous and computed locally using JavaScript's native parseInt and toString methods.
Input Validation
If you enter a digit that doesn't exist in the chosen base (e.g. '9' in binary), the tool flags it immediately with a clear error message instead of silently producing a wrong result.
100% Offline
All conversion runs in your browser using JavaScript. No data is ever sent to a server, making the tool safe for sensitive numbers from embedded systems, security research, or private code.
Free vs Pro
| Feature | Free | Pro |
|---|---|---|
| All bases 2–36 | ||
| Real-time conversion | ||
| Bit-group display | ||
| Batch file conversion | — | |
| Signed / two's complement | — | |
| REST API access | — |
Frequently Asked Questions
The tool shows results simultaneously for binary (2), octal (8), decimal (10), hexadecimal (16), base-32, and base-36. You can also enter any value from 2 to 36 in the Custom Base field for additional output.
No. You can enter hex digits in uppercase or lowercase — the tool normalises them automatically. Hex output is always shown in uppercase for readability.
The tool uses JavaScript's parseInt which safely handles integers up to 2^53 − 1. For very large numbers (cryptographic sizes), BigInt support is available in the Pro plan.
The bit-group view splits the binary representation into groups of 4 bits (nibbles), e.g. 1111 0000 instead of 11110000. This makes reading byte values, CPU flags, and binary protocols much easier.
The free tool works with non-negative integers. Signed integers and two's complement representation are available in the Pro plan.
No. Every conversion runs locally in your browser using JavaScript's built-in parseInt and toString methods. Nothing is ever transmitted to any server.