Number Base Converter — Free Online Tool
Convert numbers between binary, octal, decimal, and hexadecimal bases online for free. Enter any number in any base and see all conversions instantly.
About Number Base Converter
Number base conversion between binary (base-2), octal (base-8), decimal (base-10), and hexadecimal (base-16) is a fundamental skill in computer science, programming, and digital electronics. Our converter accepts any number in any of these four bases and instantly shows the equivalent in all other bases. Supports large numbers and shows a step-by-step conversion breakdown for educational use. Also accepts custom base inputs for bases 2 through 36 for advanced users.
Frequently Asked Questions
What bases are supported?
Binary (base-2), octal (base-8), decimal (base-10), hexadecimal (base-16), and custom bases from 2 to 36.
How do I enter a hexadecimal number?
Enter hex digits directly. Use A-F for values 10-15. The 0x prefix is optional.
How do I enter an octal number?
Enter digits 0-7 only.
What custom bases can I convert to?
Any base from 2 to 36 is supported. Bases above 10 use letters A-Z for digit values 10-35.
What is base-36 used for?
Base-36 is used for compact identifier encoding — shorter than hex for the same number.