About this tool

Binary / Hex / Decimal Converter

Convert binary, hexadecimal, decimal, and ASCII values quickly.

The Binary / Hex / Decimal Converter takes one number typed in any of those three bases and shows all of them at once, plus the matching Unicode character and the bit length. It parses with JavaScript BigInt, so values far beyond the 32-bit or 64-bit range convert exactly instead of drifting into floating-point rounding. It is built for developers reading register dumps, byte values, colour codes and protocol fields who want a single copy-ready answer rather than three separate lookups.

How to use Binary / Hex / Decimal Converter

1. 1

   Open Binary / Hex / Decimal Converter on AltFTool — it loads instantly in your browser.

2. 2

   Pick the base you are typing in from the Input format switch — Decimal, Binary or Hex — then edit the box beneath it. The tool opens on Decimal with 255 already filled in and converts as you type, so there is no convert button to press.

3. 3

   Read the five result cards: Decimal, Binary, Hexadecimal shown with an 0x prefix, Unicode character for that code point, and Bit length. A stray character replaces them with the rule you broke, such as Binary value can only contain 0 and 1.

4. 4

   Click the clipboard icon on any card to copy that value — Copied flashes in green beside the input box — or press Reset to put the tool back to Decimal 255.

Why use Binary / Hex / Decimal Converter

• Arbitrary precision, not 53-bit

  BigInt parsing means a 128-bit hash or a huge decimal converts digit-for-digit, where a normal calculator would round it.

• Every representation in one pass

  Decimal, binary, uppercase hex with the 0x prefix, the Unicode character and the bit length all update from a single input.

• Tells you why input is rejected

  Stray characters produce a specific message — binary limited to 0 and 1, hex to 0-9 and A-F, decimal to whole numbers — instead of a silent NaN.

Common use cases

• You are reading a hardware datasheet that gives a status register as 0xB4 and you need the bit pattern to see which flags are set — paste it in hex mode and read the binary 10110100 and the 8-bit length.
• A CSV export contains raw code points like 8364 and you want to know which characters they are before writing a parser — decimal mode shows the Unicode character alongside the hex 0x20AC.
• You are writing a bitmask constant and want to confirm that 1111 1111 1111 in binary really is 4095 and 0xFFF, so the mask width in your header file matches the field width in the spec.

Frequently asked questions