Number Base Converter

Convert integers between binary, octal, decimal, hex and any base 2–36 — edit any field and the rest update, BigInt-backed so large values stay exact.

Decimal (base 10)

Hexadecimal (base 16)

Octal (base 8)

Binary (base 2)

Any base

The same integer, different bases

Binary, hex, octal — only the written form changes; the value doesn't.

A number's base (radix) is just how many digit symbols it uses — binary 2, octal 8, decimal 10, hex 16. The underlying integer is identical; only its written form changes. Type into any field and the others update instantly; an invalid digit for that base highlights the field.

It's backed by JavaScript BigInt, so there's no 2⁵³ precision ceiling — paste a 200-digit number and every base stays exact. Bases 2–36 use the digits 0–9 then a–z. Negative values are fine. Everything runs in your browser.