Number Base Converter

How to Use

Select the input number base, then type your number. The tool instantly converts it to all four bases (binary, octal, decimal, hexadecimal). Click the copy button next to any result to copy it to your clipboard.

Number Base Systems

A number base (or radix) defines how many unique digits are used to represent numbers. Binary (base 2) uses 0-1 and is fundamental to computing. Octal (base 8) uses 0-7. Decimal (base 10) uses 0-9 and is the standard human system. Hexadecimal (base 16) uses 0-9 and A-F, commonly used for colors, memory addresses, and byte values.

Use Cases

• Reading memory dumps — convert hex-displayed memory contents to decimal or binary to understand values
• Color code conversion — translate CSS hex colors (#FF5733) to decimal RGB values and vice versa
• File permission calculations — expand Unix octal permissions (755, 644) to binary to see individual permission bits
• Bitwise debugging — display flags and bitmasks in binary to visually inspect the state of each bit

Mental Conversion Tricks

Each hex digit maps to exactly 4 binary digits (bits). For example, 0xF = 1111 and 0xA = 1010. Once you memorize these mappings, you can convert between hex and binary one digit at a time. Similarly, each octal digit corresponds to exactly 3 binary digits (e.g., 7 = 111, 5 = 101). For decimal-to-hex conversion, repeatedly divide by 16 and note the remainders. Memorizing commonly used values — 0xFF = 255, 0x100 = 256, 0x400 = 1024 — speeds up code reading significantly.

Privacy

All conversions happen entirely in your browser using JavaScript's BigInt for arbitrary precision. No data is sent to a server, stored, or logged.