What does XOR actually compute?

For each bit position, XOR produces a 1 when the two input bits differ (one is 0 and the other is 1), and a 0 when they match. It's the standard exclusive-or, applied independently across every bit position.

What happens if my two values have different lengths?

The shorter value is left-padded with leading zero digits until it matches the longer value's digit count, then XOR runs across every nibble-aligned bit position of that shared width.

Why is A5 XOR 3C equal to 99?

A5 is 10100101 and 3C is 00111100 in binary. Comparing bit by bit, every position differs between the two, giving 10011001, which is 99 in hex.

How is XOR different from AND and OR?

XOR is 1 only where the two bits differ, which makes it useful for detecting changes or toggling bits, whereas AND requires both bits to be 1 and OR requires only one; all three combine the same inputs very differently.

Hex XOR Calculator - Bitwise XOR of Two Hex Values

Overview

Introduction

Bitwise XOR is a fast way to spot exactly which bits differ between two hex-encoded values, or to toggle a specific set of bits.

This tool computes the bitwise XOR of two hexadecimal values, so you can see exactly which bit positions differ between them.

What Is Hex XOR Calculator?

A calculator for the bitwise XOR of two hex values: it compares the two values bit by bit and sets a 1 wherever the corresponding bits differ.

Like the other two-operand hex gate calculators in this category, it automatically left-pads the shorter operand with zero digits so both values line up bit-for-bit before combining them.

How Hex XOR Calculator Works

Both Value A and Value B are validated as hex strings, then the shorter is left-padded with leading zero digits to match the longer value's digit count.

The padded values are combined bit-by-bit with XOR, and the result is formatted as an uppercase hex string padded to that same shared width.

When To Use Hex XOR Calculator

Use it to find which bits differ between two hex-encoded values, e.g. two versions of a flag byte, or to toggle a known set of bits using a hex mask.

It's also a useful teaching tool for showing how XOR behaves on real multi-bit hex data rather than single bits.

Often used alongside Hex AND Calculator, Hex OR Calculator and Hex XNOR Calculator.

Features

Advantages

Automatically handles operands of different lengths by zero-padding, so you don't have to align widths by hand first.
Works on arbitrarily long hex values via BigInt, not limited to a fixed 8/16/32/64-bit width.
Instant, deterministic, fully client-side.

Limitations

Zero-padding the shorter operand assumes you want it treated as a smaller number within a larger field; pad manually first if your context expects different alignment.
A result bit of 1 only tells you the two source bits differed, not which one was 1; check the individual inputs if that distinction matters.

Examples

XOR of two mixed bit patterns

Input

A: A5, B: 3C

Output

A5 (10100101) XOR 3C (00111100) = 99 (10011001), a 1 at every position where the two inputs differed.

XORing a value with itself yields zero

Input

A: A5, B: A5

Output

Every bit matches when a value is XORed with itself, so the result is always all zeros.

Best Practices & Notes

Best Practices

Confirm both values are the width you intend before relying on the auto-padding, since a short operand gets left-padded with zeros.
Use the Hex XNOR Calculator on the same inputs if you actually want to see where bits agree rather than differ.

Developer Notes

Implemented with JavaScript BigInt: after zero-padding both operands to the same digit width, it computes `a ^ b` directly (no complement step), avoiding JavaScript's native 32-bit-limited bitwise operators for operands wider than 32 bits.

Hex XOR Calculator Use Cases

Diffing two hex-encoded flag bytes or register snapshots to find changed bits
Teaching or demonstrating the XOR logic gate using concrete multi-bit hex examples
Cross-checking a manually-computed XOR result

Common Mistakes

Reading an XOR result as a numeric difference; it only marks bit-level disagreement, not a magnitude or distance between the two values.
Forgetting that a short operand gets zero-padded on the left, which can change the intended meaning if it was meant to be right-aligned instead.

Tips

Try XORing a value with itself to confirm the all-zero result before relying on the tool for real data.
Compare the result with the Hex XNOR Calculator on the same inputs to see the complementary "where bits agree" view.

Hex XOR Calculator