Endianness Converter | Swap Endianness Online

Convert between big-endian and little-endian byte orders quickly and accurately.


Example: 0123456789abcdef . Input must be a hexadecimal string.

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How to Use the Endianness Converter

Learn how to swap endianness with our step-by-step guide

1

Enter Hex String

Type your hexadecimal string into the input field. The converter will automatically validate and process your input as you type.

2

Select Bit Size

Choose the appropriate bit size (16, 32, or 64 bits) to specify how the hex value should be interpreted for byte swapping.

3

Get Result

The converter will instantly display the byte-reversed hex string.

Frequently Asked Questions

Find answers to common questions about endianness and our endianness converter tool

Endianness, also known as byte order, is a concept that describes the sequence in which bytes are arranged within a larger data type (such as a word, a double word, etc.) when stored in computer memory. This arrangement matters when a computer system reads from or writes to memory, especially when this operation crosses system boundaries, such as during network communication or file I/O between systems with different endianness. There are two main types of endianness:

Big-Endian

In big-endian ordering, the most significant byte (MSB) of the word is stored in the smallest address, and the least significant byte (LSB) is stored in the largest address. A simple way to remember this is that the "big end" (the most significant part) comes first. For example, the hexadecimal number 0x1A2B3C4D stored in a 4-byte memory space would look like this: 
        
Address N  : 1A (MSB)
Address N+1: 2B
Address N+2: 3C
Address N+3: 4D (LSB)
Big-endian is commonly used in network protocols (often referred to as network byte order) and is the standard ordering in significant internet protocols.

Little-Endian

In little-endian ordering, the LSB of the word is at the smallest address, and the MSB is at the largest address. In this case, the "little end" (the least significant part) comes first. So the same hexadecimal number 0x1A2B3C4D would be stored as: 
        
Address N  : 4D (LSB)
Address N+1: 3C
Address N+2: 2B
Address N+3: 1A (MSB)
The little-endian format is notably used by Intel x86 architecture processors and therefore is widespread in personal computers.
Swapping endianness means reversing the byte order of a multi-byte value. For example, the hex value 0x12345678 in big-endian format would become 0x78563412 when swapped to little-endian, and vice versa.
You might need to swap endianness when transferring data between systems that use different byte orderings (e.g., sending data from a little-endian x86 processor to a big-endian network protocol). Misalignment can lead to data corruption or incorrect interpretation of values.
The bit size determines how many bytes are grouped together for swapping. For example, with 16-bit swapping, the hex value is treated as pairs of bytes. With 32-bit swapping, it's treated as groups of four bytes. Choose the bit size that matches the original data structure.
If your input is shorter than the selected bit size, the swapper will automatically pad it with leading zeros to reach the required length. For example, if you enter "1234" with a 32-bit size, it will be treated as "00001234".