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Free Number Base Converter | Binary, Octal, Decimal, Hexadecimal Online Tool
Convert numbers between different bases instantly with our free online number base converter. Convert binary to decimal, decimal to hexadecimal, octal to binary, and more. Supports base 2, 8, 10, 16, 32, 64, and Roman numerals. Perfect for programmers, computer science students, digital electronics, and networking. No registration required, 100% free, and works entirely in your browser.
Key Features of Our Number Base Converter
- Binary (Base 2) - Convert to/from binary numbers
- Octal (Base 8) - Convert to/from octal numbers
- Decimal (Base 10) - Convert to/from decimal numbers
- Hexadecimal (Base 16) - Convert to/from hex numbers
- Base32 - Convert to/from base32 encoding
- Base64 - Convert to/from base64 encoding
- Roman Numerals - Convert decimal to Roman numerals (1-3999)
- Copy to Clipboard - One-click copy of any converted value
- Use as Input - Swap any result back to input for further conversion
- Example Data - Quick load of sample values for testing
- Advanced Bases - Toggle visibility of Base32 and Base64
- Clear All - Reset all inputs and results
- Privacy First - All processing happens locally in your browser
- 100% Free - No watermarks, no premium tiers
- No Registration - Use instantly without signup
- Offline Support - Works without internet connection
Understanding Number Bases
Binary (Base 2)
Binary is the fundamental language of computers, using only two digits: 0 and 1. Each digit represents a bit. Binary is essential for understanding how computers store and process data, from simple calculations to complex algorithms.
Octal (Base 8)
Octal uses digits 0-7. It was commonly used in early computing and Unix file permissions. Each octal digit represents 3 bits of binary data, making it a compact representation for certain applications.
Decimal (Base 10)
Decimal is the standard number system used in everyday life, using digits 0-9. Most human-readable numbers are in decimal format.
Hexadecimal (Base 16)
Hexadecimal uses digits 0-9 and letters A-F. It's widely used in programming, color codes (like #FF0000 for red), memory addresses, and debugging. Each hex digit represents 4 bits of binary data.
Roman Numerals
Roman numerals use letters I, V, X, L, C, D, M to represent numbers. They are still used today for clock faces, book chapters, movie credits, and sporting events like the Super Bowl.
Common Use Cases for Number Base Conversion
- Programming & Debugging - Convert memory addresses and color codes
- Computer Science Education - Learn how different number systems work
- Digital Electronics - Work with binary and hex in circuit design
- Networking - Convert IP addresses and subnet masks
- Data Encoding - Use Base32 and Base64 for data transmission
- Historical Documents - Convert Roman numerals to modern numbers
Number Base Converter
Convert numbers between binary, octal, decimal, hexadecimal, and more. Perfect for programming, digital electronics, and computer science.
Number Base Converter
Enter a number in any base to convert it to all other bases.
Multiple Bases
Binary, Octal, Decimal, Hexadecimal
Privacy Focused
Your data never leaves your device.
Instant Conversion
Convert numbers instantly with one click.
Free Forever
Completely free with no registration.
How to Use Number Base Converter - Complete Guide
Select Input Base
Choose the base of your input number (Binary, Decimal, Hex, etc.).
Enter Number
Type the number in the selected base format.
Convert & Copy
Click convert to see all bases and copy any value.
Number Base Reference Guide
Common Number Bases
Quick Conversion Examples
Programming Prefixes
0b10100o120xA10Base Conversion Quick Reference
| Decimal | Binary | Octal | Hexadecimal |
|---|---|---|---|
| 1 | 1 | 1 | 1 |
| 2 | 10 | 2 | 2 |
| 3 | 11 | 3 | 3 |
| 4 | 100 | 4 | 4 |
| 5 | 101 | 5 | 5 |
| 6 | 110 | 6 | 6 |
| 7 | 111 | 7 | 7 |
| 8 | 1000 | 10 | 8 |
| 9 | 1001 | 11 | 9 |
| 10 | 1010 | 12 | A |
| 15 | 1111 | 17 | F |
| 16 | 10000 | 20 | 10 |
Frequently Asked Questions
What number bases are supported?
Binary (base 2), Octal (base 8), Decimal (base 10), Hexadecimal (base 16), Base32, Base64, and Roman numerals are supported.
Why do programmers use hexadecimal?
Hexadecimal provides a more human-readable representation of binary data. Each hex digit represents 4 bits, making it easy to convert between hex and binary.
What's the range for Roman numerals?
Roman numerals are supported for numbers 1 to 3999. Larger numbers use special notation not commonly supported in standard converters.
Is my data secure?
Absolutely! All conversions happen directly in your browser. Your data never leaves your device.
Can I convert negative numbers?
Yes, negative numbers are supported for all bases. Roman numerals only support positive numbers.
Can I use this tool offline?
Yes! Once the page loads, our Number Base Converter works completely offline. Perfect for when you don't have an internet connection.
Why Use Our Number Base Converter?
6+ Bases Supported
Binary, Octal, Decimal, Hex, Base32, Base64
Roman Numerals
Convert decimal to Roman numerals (1-3999)
Copy & Use
Copy results or use any as input
Free Forever
Completely free with no registration
Cross-Platform
Works on Windows, Mac, Linux, iOS, and Android.
No Registration
Use instantly without signing up.
Pro Tips for Number Base Conversion
- • Use binary for understanding how computers store data at the lowest level
- • Use hexadecimal for memory addresses, color codes, and debugging
- • Use octal for Unix file permissions (chmod 755)
- • Use Base64 for encoding binary data in JSON or XML
- • Copy any result and use it as input for multi-step conversions
- • Use the example buttons to quickly test the converter with common values
Number Base Converter | Binary | Octal | Decimal | Hexadecimal | Base32 | Base64
Processing: 100% client-side using JavaScript parseInt/toString • Complete privacy
Supported: Binary (2), Octal (8), Decimal (10), Hexadecimal (16), Base32, Base64, Roman Numerals
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