Number Base Converter

Convert between binary, octal, decimal, and hexadecimal

Conversion Results

Binary (2)11111111
Octal (8)377
Decimal (10)255
Hexadecimal (16)FF

What is Number Base Converter?

Number Base Converter is a free online tool that converts numbers between binary (base-2), octal (base-8), decimal (base-10), and hexadecimal (base-16) number systems. These conversions are fundamental in computer science, digital electronics, and low-level programming. Enter a number in any base and instantly see it represented in all other bases. The tool validates input for the selected base and clearly indicates errors for invalid digits. All processing happens in your browser with no server interaction. Whether you are studying computer architecture, debugging memory addresses, working with bitwise operations, or analyzing network protocols, Number Base Converter provides instant and accurate conversions.

How to Use

  1. Select the input number base.
  2. Enter a number.
  3. Conversions in all 4 bases (2, 8, 10, 16) are displayed simultaneously.

Tips & Best Practices

  • Use hexadecimal when working with memory addresses, color codes, or MAC addresses.
  • Binary is essential for understanding bitwise operations and bit flags in programming.
  • Octal is commonly used in Unix file permissions (e.g., 755, 644).
  • Group binary digits in sets of 4 from the right to easily convert to hexadecimal mentally.
  • Remember that each hex digit represents exactly 4 binary bits.

Use Cases

Programming

Convert between hex and binary for bitwise operations, flags, and low-level coding.

Networking

Convert IP addresses and subnet masks between decimal and binary representations.

Digital Electronics

Work with binary and hexadecimal values for microcontroller programming.

Education

Study and practice number system conversions for computer science courses.

FAQ

What number bases can I convert?

Conversions between Binary (2), Octal (8), Decimal (10), and Hexadecimal (16) are supported.

Can I convert negative numbers?

Currently, only positive integers can be converted.

How does number base conversion work?

The input number is first converted to decimal, then repeatedly divided by the target base, with the remainders combined in reverse order.

Is my data sent to any server?

No, all base conversions are calculated locally in your browser and no data is transmitted externally.

What do the letters A-F mean in hexadecimal?

Hexadecimal uses A=10, B=11, C=12, D=13, E=14, F=15 in addition to 0-9, representing 16 values per digit.

When is base conversion needed in programming?

Base conversion is frequently needed when working with memory addresses (hex), file permissions (octal), and bitwise operations (binary).

What number bases are supported?

Binary (base-2), octal (base-8), decimal (base-10), and hexadecimal (base-16).

Is my data collected?

No, all conversions happen in your browser. No data is sent to any server.

What digits are valid for each base?

Binary: 0-1, Octal: 0-7, Decimal: 0-9, Hexadecimal: 0-9 and A-F.

Why is hexadecimal used in programming?

Hexadecimal is compact (each digit = 4 bits) and easy to convert to/from binary, making it ideal for memory addresses and color codes.

What is octal used for?

Octal is primarily used for Unix/Linux file permissions (e.g., chmod 755) where each digit represents 3 permission bits.

Can I convert very large numbers?

Yes, the tool handles large numbers within JavaScript's safe integer range.

How do I read binary numbers?

Read right to left: each position represents a power of 2. For example, 1010 = 8+0+2+0 = 10 in decimal.

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