Free Number System Converter
Programmers live in hexadecimal, digital circuits speak binary, and file permissions hide in octal. This free number system converter translates between all four bases instantly — with arbitrary-precision integers, so even huge values convert exactly.
Value in all number systems
| System | Value |
|---|
How to Use the Number System Converter
- Enter your number — prefixes like 0b, 0o and 0x are accepted.
- Select the base your number is written in.
- Read all four representations in the table, plus the bit length.
- Copy the results with one click for your code or notes.
Features
Binary, octal, decimal and hexadecimal conversion using BigInt for unlimited precision. Accepts 0b/0o/0x prefixes and negative numbers, shows bit length, and groups binary digits in fours for readability.
Benefits & Use Cases
Developers debugging bitmasks, students learning bases, sysadmins decoding permissions, and CTF players all get exact answers for values of any size. No floating-point rounding, ever.
Tips
Each hex digit is exactly 4 bits: FF = 1111 1111 = 255. Octal digits map to 3 bits each, which is why Unix permissions (like 755) fit octal so neatly.
Frequently Asked Questions
How do I convert binary to decimal?
Type the binary number, set the input base to binary, and read the decimal row. For example, 11111111 = 255.
How do I convert hex to decimal?
Select hexadecimal as the input base and type the value — FF becomes 255, with 0x prefixes accepted.
What is the largest number it can convert?
There is no practical limit: arbitrary-precision integers handle hundreds of digits exactly.
Why do programmers use hexadecimal?
It is compact shorthand for binary — two hex digits per byte — making memory addresses and color codes readable.
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