Number Base Converter

Convert between binary, octal, decimal, hexadecimal and custom number bases instantly

Input
Conversion Results
Binary (2)
Octal (8)
Decimal (10)
Hexadecimal (16)

Input Base

What is Number Base Conversion?

'

Number base conversion is the process of changing a number from one numeral system to another. Common bases include binary (base-2), octal (base-8), decimal (base-10), and hexadecimal (base-16).

In computer science, binary is the most fundamental number system since all data inside computers is stored in binary. Hexadecimal is widely used for memory addresses and color values because it is more compact and readable than binary. Octal is commonly used in Unix file permissions and other contexts.

'

How to Use

  1. Enter the number you want to convert in the input field (e.g., 255, FF, 11111111)
  2. Select the base of your input number: binary, octal, decimal, hexadecimal, or a custom base
  3. The tool automatically converts the input to binary, octal, decimal, and hexadecimal results
  4. Click the "Copy" button next to any result to copy it to your clipboard

Features

Multi-base OutputDisplays binary, octal, decimal, and hexadecimal results simultaneously
Custom BaseSupports any base from 2 to 36 for special conversion needs
Real-time ConversionResults update instantly as you type, no button click needed
One-click CopyCopy button next to each result for quick use

Conversion Examples

Decimal → Hexadecimal

255FF

Commonly used in CSS color values, e.g., #FF0000 for red

Binary → Decimal

11111111255

Maximum value of 8-bit binary, i.e., the largest unsigned byte

Hexadecimal → Binary

1A3F1101000111111

Every 4 binary digits correspond to 1 hexadecimal digit

Octal → Hexadecimal

377FF

Unix permission 377 (rwxrwxrwx) equals hex FF

Custom Base

ZZ (base-36)1295 (decimal)

Base-36 uses 0-9 and A-Z, maximum is ZZ

FAQ

Q: What are binary and hexadecimal?

A: Binary uses only 0 and 1, and is the foundation of computer arithmetic. Hexadecimal uses 0-9 and A-F (16 characters total), commonly used in programming for colors, memory addresses, etc. Every 4 binary digits correspond to exactly 1 hexadecimal digit.

Q: How do I manually convert between bases?

A: For example, converting decimal 255 to hex: 255÷16=15 remainder 15, 15÷16=0 remainder 15. Reading remainders bottom-up, 15 equals F in hex, so the result is FF. This tool automates these calculations for you.

Q: Which bases are supported?

A: This tool supports any base from 2 to 36. Bases 2-10 use digits 0-9, and bases 11-36 additionally use letters A-Z (case-insensitive). For example, hexadecimal uses 0-9 and A-F.