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Reverse Hex

Enter a hex string to instantly reverse its byte order — useful for little-endian to big-endian conversions and binary data inspection.

Last updated: May 30, 2026

Client-Side Processing
Input Data Stays on Device
Instant Local Execution
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What is Reverse Hex?

Different computer architectures and network protocols store multi-byte values in different byte orders (endianness). Big-endian systems store the most significant byte first; little-endian systems store the least significant byte first.

Reversing a hex string's byte order is a fundamental operation when: - Reading binary files created on a different-endian architecture. - Converting network byte order (big-endian) to host byte order (little-endian) for x86 systems. - Debugging binary data in hex dumps where the byte order is unexpected.

For example, the hex value C0A80101 (192.168.1.1 in big-endian) becomes 0101A8C0 after a byte-order reversal.

This tool works on pairs of hex digits (bytes) — the smallest addressable unit — swapping the sequence of bytes while keeping each byte's internal nibble order intact.

How to Use Reverse Hex

1

Type or paste your hex string in the input field (with or without 0x prefix).

2

The byte-reversed output appears instantly.

3

Use the copy button to copy the reversed hex with or without the 0x prefix.

4

Click "Load Sample" to see an example.

Common Use Cases

  • Converting little-endian hex values from Windows registry or binary files to big-endian.
  • Reversing network packet byte order for protocol analysis.
  • Preparing hex values for assembly language or embedded systems code that expects a specific byte order.
  • Debugging binary data structures where fields are in unexpected byte order.

Example Input and Output

The hex value C0A80101 (big-endian for 192.168.1.1) reversed to byte order 0101A8C0.

Hex Input
C0A80101
Byte-Reversed Hex
0101A8C0

Data Privacy

All conversions run entirely in your browser. No hex data is sent to any external server.

Frequently Asked Questions

What is byte-order reversal (endian swap)?

Endian swap reverses the order of bytes in a multi-byte value. For a 4-byte hex value AABBCCDD, the byte-swapped result is DDCCBBAA. Each individual byte (two hex digits) stays intact; only the order of the bytes changes.

What happens if I enter an odd number of hex digits?

An odd number of hex digits cannot form complete bytes. This tool pads the input with a leading zero to make it even before reversing, so "FFF" becomes "0FFF" → reversed "FF0F".

Is this the same as reversing the string character by character?

No. Character reversal of "AABB" gives "BBAA", which is the same result only by coincidence for 2-byte values. For longer values like "AABBCC", character reversal gives "CCBBAA" while byte reversal gives "CCBBAA" — they happen to match here. But for "AABBCCDD", character reversal gives "DDCCBBAA" which equals byte reversal only if each byte is 2 chars. The byte-reversal approach is always safe and correct.

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