Decimal Converter
Convert between decimal, binary, octal, and hexadecimal — instantly and privately in your browser.
How it works: Enter a number in any base (decimal, binary, octal, or hex) and this tool instantly converts it to all other bases. The Unicode/ASCII row shows the character mapped to that code point when valid. All calculations run locally in your browser.
Private by design
All conversions happen locally in your browser. Your numbers never leave your device.
Four-way conversion
Enter a number in any base and see equivalent values in decimal, binary, octal, and hex.
ASCII / Unicode lookup
When a code point is valid, the matching Unicode character is shown for quick reference.
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 decimal 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 decimal converter and why would I need one?
A decimal converter translates numbers between different numeral systems — decimal (base 10), binary (base 2), octal (base 8), and hexadecimal (base 16). Developers, students, and embedded systems engineers use them daily when reading memory dumps, writing bitwise operations, configuring color hex codes, or debugging network packets.
›How do I convert binary to decimal?
Select the Binary input mode, enter your binary number (e.g. 11111111), and the tool instantly shows the decimal equivalent (255). You can copy any output with one click. The conversion happens locally using standard JavaScript integer parsing.
›How do I convert decimal to hexadecimal?
Select the Decimal input mode, type your decimal number (e.g. 48879), and the tool will display the hex value (BEEF) in the Hexadecimal card. If the decimal value maps to a valid Unicode code point, the character is shown too.
›Can this tool convert negative numbers or fractions?
This tool converts integer values between bases. Negative decimal values are supported. Fractional numbers (with a decimal point) are not currently supported because binary/octal/hex fractional representations require different algorithms. For fractions, round to the nearest integer first.
›What is the difference between octal, decimal, and hexadecimal?
Octal uses digits 0–7 (base 8) and was common in early Unix file permissions. Decimal uses 0–9 (base 10) and is the everyday number system. Hexadecimal uses 0–9 and A–F (base 16) and is dominant in computing because one hex digit represents exactly four binary bits, making it compact for memory addresses, colors, and byte values.
›Does this tool send my numbers to a server?
No. All conversion logic runs entirely in your browser using standard JavaScript parseInt and toString methods. Your input is never transmitted, logged, or stored on any server.
›What is the maximum number this converter can handle?
The tool uses JavaScript's 32-bit signed integer range by default for strict parsing. Very large integers may lose precision due to JavaScript's floating-point number representation. For cryptographic or scientific use cases requiring arbitrary precision, use a specialized big-integer library.
›Why do I see a Unicode / ASCII character in the output?
When the converted decimal value falls within a valid Unicode code point range (0 to 0x10FFFF), the tool displays the corresponding character. This is useful for developers working with character encodings, emoji code points, or escape sequences.
›Is hex the same as hexadecimal?
Yes. 'Hex' is simply shorthand for hexadecimal, the base-16 numbering system that uses digits 0–9 and letters A–F. It is the standard way to represent colors in CSS (#FF5733), memory addresses, MAC addresses, and binary data in a human-readable form.
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