Number Base Converter
Convert numbers between decimal, hexadecimal, binary, and octal instantly. Supports integers up to 53-bit precision. Runs entirely in your browser.
Frequently Asked Questions
What number bases are supported?
Decimal (base 10), hexadecimal (base 16), binary (base 2), and octal (base 8). Type in any field and all others update instantly.
What is the maximum number I can convert?
JavaScript integers are precise up to 2^53 − 1 (about 9 quadrillion in decimal, or 0x1FFFFFFFFFFFFF in hex). Numbers larger than this may lose precision.
Why do programmers use hexadecimal?
Hex maps cleanly to binary — each hex digit represents exactly 4 binary bits. This makes it compact and easy to inspect memory addresses, colour values, byte sequences, and bitfields.
Is my data private?
Yes — completely. Everything runs locally in your browser. Nothing is sent to any server, and nothing is retained after you close the tab.
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