Number Base Converter
Convert numbers between decimal, hexadecimal, binary, and octal. Enter any value in any base and all others update instantly. Handles large integers and shows the calculation.
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Ctrl + Enter to run · Recent brings back your last inputs · Everything stays in this browser
Number Base Converter: questions
What is the maximum number supported?
JavaScript safe integers up to 2^53-1. For larger numbers, use a dedicated big-integer library.
Can I enter hex with 0x prefix?
Yes — the hex field accepts values with or without the 0x prefix.
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