Hex to Binary Converter

How to use the hex to binary

1. Type or paste a hexadecimal string into the input field. You may include a 0x prefix; it will be ignored during conversion.
2. Choose how to group the output bits: no grouping, every 4 bits (one nibble) or every 8 bits (one byte).
3. Toggle the Add 0b prefix checkbox if you need the standard binary literal format used in many programming languages.
4. Select uppercase or lowercase for the prefix letters. The binary digits themselves are always 0 and 1.
5. The binary result updates instantly as you type. Copy it directly from the output area.

How hex to binary conversion works

Each hexadecimal digit maps to exactly four binary digits (a nibble). Because 16 is a power of 2, the conversion is direct: you replace each hex character with its four-bit equivalent rather than performing arithmetic division.

The mapping is fixed:

To convert 1A3F, replace each digit: 1 becomes 0001, A becomes 1010, 3 becomes 0011 and F becomes 1111. Concatenating them gives 0001101000111111. Leading zeros on the very first nibble are typically dropped unless you need a fixed bit width, so the result is 1101000111111.

Reference table for all hex digits

This table shows every valid hexadecimal character and its four-bit binary equivalent. Use it to verify manual conversions or to understand the pattern behind the hex to binary mapping.

Why group bits into nibbles or bytes

A long string of ones and zeros is difficult to read. Grouping the output makes it easier to cross-reference with the original hex value or to identify specific fields in a binary protocol.

• Nibble grouping (4 bits): Each group corresponds to one hex digit. This is the most natural way to read a hex to binary conversion because you can map each group back to its source character.
• Byte grouping (8 bits): Useful when working with memory addresses, network packets or file formats where data is organized in bytes. Two hex digits always form one byte.
• No grouping: Produces a continuous string suitable for pasting into code or feeding into another tool like a bitwise calculator.

Handling large hexadecimal values

Standard JavaScript numbers lose precision beyond 53 bits. This converter uses BigInt internally, so you can paste hex strings of any length, such as cryptographic hashes or UUIDs, and get an exact binary representation without rounding errors.

For example, a SHA-256 hash is 64 hex characters long, representing 256 bits. Converting it with standard floating-point math would corrupt the least significant bits. With BigInt, every bit is preserved exactly. If you need to work with the numeric value of that hash in base 10, use the hex to decimal tool instead.

Common mistakes to avoid

When converting hex to binary manually, a few errors come up frequently:

• Dropping leading zeros within a nibble: The hex digit 3 must become 0011, not 11. Only the leading zeros of the very first digit may be dropped.
• Confusing hex letters with variables: In hex, A through F represent values 10 through 15. They are not algebraic variables.
• Mixing up prefixes: 0x denotes hexadecimal in C-style languages, while 0b denotes binary. Adding 0x to a binary string will cause parser errors in most environments.
• Ignoring case sensitivity in strict parsers: While this tool accepts both upper and lowercase hex input, some programming languages or protocols require a specific case.

Worked examples