Binary / Hex / Decimal Converter

Convert exact integers between binary, decimal, and hexadecimal with strict parsing and BigInt-safe results.

Decimal input

Optional + or -, then digits 0 through 9 only.

Enter a decimal integer. Use an optional + or - followed by digits 0 through 9 only.

Input base

Binary(bin)

Decimal(dec)

Hexadecimal(hex)

Group binary digits

Show binary results in 4-bit chunks for easier binary-to-hex reading.

1 hex digit = 4 bits. Negative values use a minus sign, not two's complement.

Binary

Displayed in 4-bit groups; copied without spaces.

Decimal

Hexadecimal

Binary, Hex, and Decimal Converter

Toolzy's binary / hex / decimal converter is built for strict integer conversion, not permissive parsing. Choose the input base explicitly, enter a whole number, and the tool synchronizes binary, decimal, and hexadecimal outputs in one pass.

This helps when you need quick answers for searches like binary to decimal, decimal to binary, hex to decimal, or hex to bin, but still want rules that behave predictably for code, docs, and debugging.

What This Converter Accepts

Binary input accepts an optional + or -, an optional matching 0b prefix, and only 0 or 1 digits.
Decimal input accepts an optional sign and digits 0-9 only.
Hexadecimal input accepts an optional sign, an optional matching 0x prefix, and digits 0-9 plus letters A-F.
Leading and trailing whitespace is trimmed, but internal spaces, underscores, commas, apostrophes, exponent notation, and decimal points are rejected.

Canonical Output Rules

Outputs are normalized bare values with no prefixes.
Hexadecimal output is always uppercase.
Binary output has no leading zero padding, except for 0 itself.
Signed zero inputs like -0, +0, -0b0, and -0x0 normalize to 0.

Exact Results For Large Integers

The converter uses BigInt-safe integer logic in the browser, so values larger than Number.MAX_SAFE_INTEGER stay exact. For example, decimal 18446744073709551615 converts cleanly to hexadecimal FFFFFFFFFFFFFFFF without rounding or scientific notation.

Negative Numbers Vs. Two's Complement

Negative results are shown with a leading minus sign in every base. That means decimal -15 becomes binary -1111 and hexadecimal -F.

This tool does not guess or display two's-complement bit patterns, because those require an explicit bit width. It keeps the numeric value separate from machine representation.

Quick Reference

11111111 in binary = 255 in decimal = FF in hexadecimal
255 in decimal = 11111111 in binary = FF in hexadecimal
0x2A in hex = 42 in decimal = 101010 in binary
1 hex digit = 4 binary bits

Troubleshooting

Why does 0x1010 fail in binary mode? — Prefixes only work when they match the selected input base. Switch the base to Hexadecimal to parse 0x input.

Why does 123_456 fail? — v1 uses strict integer parsing and rejects separators such as underscores, spaces, commas, and apostrophes.

Why does -15 show -1111 instead of a fixed-width bit pattern? — The converter shows signed integer values only. Two's-complement output is intentionally out of scope unless a width is specified.