Why do programmers use hex?

Each hex digit maps to exactly 4 binary bits, so two hex digits = one byte. Reading 0xFF is easier than 11111111.

Digits 0-9 + letters A-Z. Often used for compact slug encoding or short URLs.

What's the largest number I can convert?

The tool handles arbitrary precision — paste a 1000-digit number and it will convert without overflow.

Are negative numbers supported?

Yes — sign-magnitude representation. Two's complement is a separate option for fixed-width binary.

Does it handle fractional values?

Yes — convert 0.1 from decimal to binary and see the recurring representation (0.0001100110011... in binary).

Number Base Converter

Binary ↔ Octal ↔ Decimal ↔ Hex ↔ any base 2–36

Developer

Number Base Converter

Binary ↔ Octal ↔ Decimal ↔ Hex ↔ any base 2–36

Number Input base

Custom output base (2–36)

Result

About this tool

Convert a number between binary, octal, decimal, hexadecimal, and any custom base from 2 to 36. Uses arbitrary-precision BigInt arithmetic — handles numbers far larger than 64 bits with no rounding. Click any output to copy.

Formula

Each digit position d in base b contributes d × bⁿ

Decimal: 255 = 2·10² + 5·10¹ + 5·10⁰

Binary: 11111111 = 1·2⁷ + 1·2⁶ + … + 1·2⁰ = 255

Hex: FF = 15·16¹ + 15·16⁰ = 255

How to use

1 Type the number into the input field.
2 Pick the input base — what base your number is currently in.
3 All four standard bases (binary, octal, decimal, hex) appear instantly.
4 For an arbitrary base (e.g. base 36, base 7), use the custom output box.
5 Click any output card to copy that representation.

Examples

255 (decimal) → hex	FF
11111111 (binary) → decimal	255
DEADBEEF (hex) → decimal	3735928559
1000 (decimal) → base 36	rs
-15 (decimal) → binary	-1111

Frequently asked questions

Base 36 uses digits 0–9 and letters a–z (10 + 26 = 36). Going higher requires inventing new symbols, which is non-standard.

Yes — prefix the input with a minus sign. Output is shown with the same sign. For two's complement / bitwise representation use the Developer Calculator.

Limited only by browser memory. Toolenza uses BigInt, so a 100-digit decimal number converts cleanly. Large numbers may take a few milliseconds.

This tool is for pure base conversion of any size. The Developer Calculator focuses on bitwise operations and 64-bit arithmetic.

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