Number Base Converter
Convert numbers between decimal, binary, hexadecimal, and octal — all four shown at once.
How to use this tool
- 1Enter a number in the Input field.
- 2Select the source base from the 'From base' dropdown: Decimal, Binary, Hexadecimal, or Octal.
- 3All four representations appear instantly in the grid.
- 4Click Copy next to any value to copy it.
About Number Base Converter
Working with different number bases is fundamental in programming, digital electronics, and computer science. This converter accepts a number in any of four bases and shows all four representations simultaneously: Decimal (base 10), Binary (base 2), Hexadecimal (base 16, uppercase), and Octal (base 8). The conversion uses JavaScript's parseInt(input, base) to parse the input and .toString(base) to format each output. If the input contains characters invalid for the selected base (e.g. '2' in binary), an error message is shown. Each output card has its own Copy button. The source base card is highlighted with a ring. Developers converting memory addresses from hex to decimal, students learning binary arithmetic, and engineers working with bitfields are the primary users. Runs entirely in your browser.
Frequently asked questions
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