📖 What is Number Base Converter?
Number Base Converter transforms numbers between different numeral systems — binary (base 2), octal (base 8), decimal (base 10) and hexadecimal (base 16). Enter a number in any base and see it converted to all others instantly. Use it for programming, networking (subnet masks), color codes, or learning number systems. Everything runs in your browser.
💡 Example
Output
Binary: 11111111
Octal: 377
Hex: FF
🛠️ Common Use Cases
- Converting between hex and binary for bitwise operations
- Working with color codes (hex to decimal RGB values)
- Understanding subnet masks and IP addressing
- Debugging binary data and memory addresses
- Learning numeral systems and base conversion
📝 Common Bases
- Binary (2) — used in hardware, bitwise operations, permissions (chmod)
- Octal (8) — Unix file permissions (755, 644)
- Decimal (10) — human-readable numbers
- Hexadecimal (16) — colors (#FF0000), memory addresses, MAC addresses
⚠️ Common Mistakes
- Confusing 0x and 0b prefixes — 0xFF is hex (255), 0b1111 is binary (15). Without the prefix, the base is ambiguous.
- Octal in JavaScript — leading zeros (077) are octal in some contexts. Use 0o77 for explicit octal in modern JS.
- Case sensitivity in hex — FF and ff are the same value. Hex digits A-F are case-insensitive.
❓ Frequently Asked Questions
What is hexadecimal used for? ▾
Hex is a compact way to represent binary data. Each hex digit represents 4 bits, so a byte (8 bits) is exactly 2 hex digits. It is used for colors, memory addresses, MAC addresses and encoding.
How do I convert binary to decimal? ▾
Each binary digit represents a power of 2. For example, 1101 = 8+4+0+1 = 13. This tool does it instantly.
What are octal numbers used for? ▾
Octal is primarily used in Unix file permissions: 755 means rwxr-xr-x, 644 means rw-r--r--.
Is my data private? ▾
Yes — all processing runs entirely in your browser. Your data is never sent to any server.
Is this tool free? ▾
Completely free — no login, no usage limits, works offline once loaded.
Yes — completely free, no login required, no usage limits.
Is my data private? ▾
Yes — all processing runs in your browser. Your data is never sent to any server.
Does it work offline? ▾
Yes — once the page is loaded, the tool works without an internet connection.