Number Base Converter
Convert between decimal, hexadecimal, binary, and octal — all at once, any size integer.
Decimal (base 10)
255
Hexadecimal (base 16)
FF
Binary (base 2)
1111 1111
Octal (base 8)
377
Number base conversion explained
Computers work in binary (base 2). Hexadecimal (base 16) is a compact human-readable form — each hex digit is exactly 4 bits. Octal (base 8) was popular in older systems and Unix file permissions. This converter handles arbitrarily large integers using JavaScript's BigInt, so there's no 32-bit or 64-bit overflow. For individual conversion tools, try Decimal to Binary or Hex to Decimal.
Private & free — this tool runs entirely in your browser.
Recommended: IndieKit — Ship your Next.js startup in days.affiliate
Related Converters tools
JSON to YAML
Convert JSON into clean, readable YAML instantly.
YAML to JSON
Convert YAML configuration into valid JSON.
JSON to CSV
Flatten a JSON array of objects into CSV rows.
CSV to JSON
Parse CSV with headers into a JSON array of objects.
JSON to XML
Convert JSON structures into nested XML markup.
HWB to HEX Converter
Convert an HWB color to HEX.
JSON to SQL
Turn a JSON array of objects into SQL INSERT statements.
CSV to XML
Convert CSV rows into structured XML records.