Number Base Converter
Convert numbers between binary, octal, decimal, and hexadecimal instantly. Supports custom bases from 2 to 36.
What is a number base (radix)?
A number base, also called radix, defines how many unique digits a positional numeral system uses. For example, binary uses 2 digits (0–1), decimal uses 10 digits (0–9), and hexadecimal uses 16 digits (0–9 and A–F).
How do I convert decimal to binary?
Enter the decimal number in the input field, set the source base to 10, and the tool will instantly display the binary (base 2) equivalent. The process repeatedly divides by 2 and records remainders.
How do I convert binary to hexadecimal?
Input your binary number with source base 2. The converter groups binary digits into sets of four (starting from the right) and maps each group to its hex equivalent (0–F).
What is hexadecimal used for?
Hexadecimal (base 16) is widely used in computing for memory addresses, color codes in web design (e.g., #FF5733), MAC addresses, and representing binary data in a compact, human-readable format.
What is octal used for?
Octal (base 8) was historically used in early computing systems and is still used today for Unix file permissions (e.g., 755) and in some programming languages for literal constants.
What number bases does this tool support?
This converter supports all bases from 2 to 36. Common presets include binary (2), octal (8), decimal (10), and hexadecimal (16). You can also enter any custom base up to 36.
Can I convert negative numbers or decimals?
This tool handles negative integers with a minus sign. Fractional parts can also be converted for bases that support them.
How do I convert between two non-decimal bases?
Enter the number in its source base, then read the result in your target base. The tool converts through decimal internally, so you can go directly from any base to any other base.
What are the digits for bases above 10?
For bases above 10, letters are used as digits: A=10, B=11, C=12, ... F=15 for hexadecimal, and so on up to Z=35 for base 36.
Is this tool free to use?
Yes, this number base converter is completely free. No registration or download is required — just open it in your browser and start converting.
Does this tool work offline?
Once the page is loaded, all conversions happen locally in your browser. No data is sent to any server, ensuring your inputs remain private.
What is the difference between signed and unsigned binary?
Unsigned binary represents only non-negative values. Signed binary uses the most significant bit as a sign indicator (0 for positive, 1 for negative), commonly using two's complement representation.
How to Use Number Base Converter
Convert numbers between binary, octal, decimal, and hexadecimal — or any custom base from 2 to 36 — instantly in your browser. The conversion runs entirely locally, with no data sent anywhere.
- Type your value into the Number: field.
- Select the source base — BIN (2), OCT (8), DEC (10), or HEX (16) — or enter a Custom base (2-36) for less common radixes.
- Read the equivalent values in all other bases, updated live as you type.
- Use letters A–Z for digit values above 9, for example Z3F is valid in base 36.
Hex digits accept both cases, but sticking to lowercase keeps converted output consistent when pasting into code.
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