Base Converter

Enter a number and choose its base; this tool shows its binary, octal, decimal and hexadecimal forms at once. It uses BigInt, so even very long numbers don't lose precision the way parseInt would.

Writing firewall rules, setting permission bitmasks (like chmod 755), tweaking color values or reading low-level debug output constantly means converting between base 2 / 8 / 10 / 16. All local, never uploaded.