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Online Number Base Converter

Convert between binary, octal, decimal, and hexadecimal

Real-time conversion
Multiple bases
Reference table
Base Converter
Common Values Reference
DecimalBinaryOctalHexadecimal
0000
1111
21022
410044
81000108
16100002010
321000004020
64100000010040
1281000000020080
25511111111377FF
256100000000400100
1024100000000002000400
Usage Guide

What are number bases?

A number base is a counting system. Binary (0-1) is used by computers, octal and hexadecimal simplify binary representation, and decimal is our everyday counting system.

Common Use Cases

  • • Color code conversion
  • • Memory address analysis
  • • Permission value calculation
  • • Network debugging

Need to convert numbers between different bases quickly? Our free online number base converter provides instant conversion between binary, octal, decimal, and hexadecimal number systems. Whether you are a software developer debugging memory addresses, a computer science student learning numeral systems, or a network engineer working with IP addresses and subnet masks, this tool makes base conversion effortless. Simply enter a value in any base, and see the equivalent values in all other bases instantly. The real-time conversion feature eliminates manual calculations and reduces errors. Our comprehensive reference table shows common values across all bases, making it easier to verify your conversions and understand the relationships between different number systems.

Understanding Number Bases

A number base, or radix, determines how many unique digits are used to represent numbers. The decimal system (base 10) uses digits 0-9 and is the system we use daily. Binary (base 2) uses only 0 and 1, forming the foundation of digital computing. Octal (base 8) uses digits 0-7 and was historically used in computing. Hexadecimal (base 16) uses 0-9 and A-F, providing a compact way to represent binary data. Each base has specific applications: binary for computer logic, hexadecimal for memory addresses and color codes, and octal for Unix file permissions.

How to Use the Number Base Converter

  • Enter a number in any of the four input fields (binary, octal, decimal, or hexadecimal)
  • The tool instantly converts and displays the equivalent value in all other bases
  • Use the copy button next to each field to copy the converted value
  • Reference the common values table to verify your conversions
  • Invalid characters for the selected base will trigger an error message

Binary: The Language of Computers

Binary (base 2) is the fundamental number system for all digital computers. Every piece of data, from text to images to programs, is ultimately stored and processed as binary. Each binary digit (bit) can be either 0 or 1, representing electrical off and on states in computer circuits. Understanding binary is essential for low-level programming, debugging, and understanding how computers work. Common binary values to memorize: 8 bits = 1 byte, which can represent values from 0 to 255 (00000000 to 11111111).

Hexadecimal: Compact Binary Representation

Hexadecimal (base 16) provides a human-friendly way to represent binary data. Each hex digit corresponds to exactly 4 binary digits (bits), making conversion between hex and binary straightforward. Hex is extensively used in programming for memory addresses, color codes (like #FF5733), MAC addresses, and debugging. In web development, colors are typically specified in hex format. Learning to read and convert hex is an essential skill for developers working with low-level systems or network protocols.

Practical Applications of Base Conversion

Number base conversion has many real-world applications. Web developers use hex for CSS colors and RGB values. System programmers analyze memory dumps in hexadecimal. Network engineers work with binary for IP addressing and subnetting. Unix/Linux users encounter octal for file permissions (like chmod 755). Security professionals analyze binary data when reverse engineering. Understanding these conversions helps you work more efficiently across different computing domains.

FAQ

Q: Why do computers use binary?

A: Computers use binary because electronic circuits have two stable states: on (1) and off (0). This makes binary the most reliable and efficient way to store and process data electronically. While humans find decimal more natural, binary is the native language of all digital hardware.

Q: What do A-F mean in hexadecimal?

A: In hexadecimal, the letters A through F represent values 10 through 15. A=10, B=11, C=12, D=13, E=14, F=15. This allows hexadecimal to represent 16 different values (0-15) with a single digit. The letters can be uppercase or lowercase - 1F and 1f represent the same value.

Q: How do I convert binary to decimal manually?

A: To convert binary to decimal, multiply each digit by its position value (powers of 2, starting from 0 on the right) and sum the results. For example, binary 1011 = (1x8) + (0x4) + (1x2) + (1x1) = 8 + 0 + 2 + 1 = 11 in decimal.

Q: What is octal used for today?

A: Octal is primarily used in Unix/Linux file permissions. Commands like chmod use octal values where each digit represents read (4), write (2), and execute (1) permissions. For example, chmod 755 sets rwx for owner, rx for group and others. Octal was also historically used in early computing systems.

Q: How are hex colors converted?

A: Hex colors like #FF5733 contain three pairs of hex digits representing Red, Green, and Blue values. FF (255 decimal) is full red, 57 (87 decimal) is the green component, and 33 (51 decimal) is blue. Converting each pair to decimal gives you the RGB values: rgb(255, 87, 51).