Is the number I enter sent anywhere?

No. Conversion happens entirely in your browser using JavaScript BigInt. No network request is made and nothing is stored.

Is there a size limit on the numbers?

Practically no. The tool uses BigInt rather than floating-point numbers, so values far beyond 2^53 convert exactly, with no rounding or precision loss.

Can I convert negative or fractional numbers?

No. The tool accepts non-negative integers only — digit validation rejects minus signs and decimal points, since bases 2, 8, 10, and 16 fields each allow only their own digit set.

Number Base Converter

Overview

Binary, octal, decimal, and hex are the four bases developers actually use — bit masks, Unix permissions, everyday values, and memory addresses or color codes. This tool keeps all four representations in sync: edit any one field and the other three recompute instantly. Because it is built on BigInt, values of any length convert exactly, unlike converters limited to 53-bit floats.

How to use

Type an integer into any of the four fields: Binary (base 2), Octal (base 8), Decimal (base 10), or Hex (base 16).
The other three fields update as you type.
If a character is not valid for that field’s base, an error such as Invalid hex digits appears and the other fields keep their last valid value.

Examples

Decimal 255 → Binary 11111111, Octal 377, Hex ff
Hex deadbeef → Decimal 3735928559
Decimal 18446744073709551615 (2^64 − 1) → Hex ffffffffffffffff — exact, no rounding

Notes

Enter digits only — prefixes like 0x, 0b, or 0o are not accepted; the field itself determines the base. Hex input is case-insensitive.