Number Base Converter
Convert between binary, octal, decimal, and hexadecimal — instantly and privately in your browser.
How it works: Choose a source and target number base, then enter your value. The tool instantly converts between binary, octal, decimal, and hexadecimal. The bit visualization shows the binary representation with each bit highlighted. All processing is done locally in your browser — nothing is sent to a server.
Bidirectional conversion
Convert from any base to any other base with a single click. Swap source and target instantly.
Private by design
All calculations happen locally in your browser. Your numbers never leave your device.
Bit visualization
See the binary representation of your number with highlighted bits and byte boundaries.
How number base conversion works
Computers natively operate in binary (base 2) because electronic circuits have two states: on and off. But long strings of 1s and 0s are hard for humans to read, so we use shorthand number systems. Octal (base 8) groups three bits into one digit. Hexadecimal (base 16) groups four bits into one digit, making it especially compact for representing bytes, memory addresses, and color codes. Decimal (base 10) is the everyday system most people use.
A number base converter bridges these worlds. You type a number in one base, and the tool uses standard mathematical conversion algorithms to express that same value in every other base. For example, the decimal value 255 becomes 11111111 in binary, 377 in octal, and FF in hexadecimal.
Common use cases for base conversion
Web developers use hex every day in CSS color codes like #3B82F6. Network engineers read MAC addresses in hex. Security researchers inspect binary data and memory offsets in hex during reverse engineering. Computer science students practice binary and hex when learning about bitwise operators and data representation. Embedded systems programmers configure registers using hex and binary masks.
No matter your background, converting between bases is a frequent task. This tool makes it effortless with real-time results, one-click copying, and a clean, distraction-free interface.
Frequently asked questions
›What is a number base converter?
A number base converter translates a number from one numeral system to another — for example, from binary (base 2) to decimal (base 10) or hexadecimal (base 16). It helps developers, students, and engineers work across different representations.
›How do I convert binary to decimal?
Select Binary as the source base and Decimal as the target base, then enter your binary number (e.g. 101010). The tool instantly shows the decimal equivalent.
›How do I convert hex to binary?
Select Hexadecimal as the source base and Binary as the target base, then type your hex value. The tool outputs the full binary representation with optional bit visualization.
›Is this tool safe to use with sensitive data?
Yes. All calculations run entirely in your browser. No data is sent to any server.
›What bases are supported?
The tool supports binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16) conversions in any direction.
›What is the bit visualization?
The bit visualization shows the binary representation of your number with each individual bit displayed. Set bits (1s) are highlighted to make the binary structure easy to read.
›Can I convert negative numbers?
Yes. Enter a negative decimal number and the tool will show its signed representation where applicable.
›Does the tool support prefixes like 0x or 0b?
Yes. You can enter values with standard prefixes like 0x for hex, 0b for binary, and 0o for octal. The tool strips them automatically.
›What is the maximum number supported?
The tool supports numbers up to JavaScript's MAX_SAFE_INTEGER (9,007,199,254,740,991), which is well beyond typical computing needs.
›Can I copy results to my clipboard?
Yes. Every output card has a copy button. Click it to copy the formatted value with its base prefix (e.g., 0xFF).
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