XOR Cipher Tool
Encrypt and decrypt text using XOR with a custom key - fully client-side with our free XOR cipher tool. Supports UTF-8, hexadecimal, and Base64 formats for both input and key. Features a visual byte-by-byte XOR operation table showing the exact calculation for each byte. No signup required - all processing runs locally in your browser.
Enter your text and key, choose the input/key/output formats, and click Apply XOR. XOR is symmetric - applying the same key twice recovers the original text. All processing runs locally in your browser with no data sent to any server.
Why Use Our XOR Cipher Tool?
Instant XOR Cipher Operations
Apply XOR encryption and decryption instantly in your browser. Our XOR cipher tool processes any length of text in milliseconds - no waiting, no server round-trips, no ads.
Secure XOR Cipher Tool Online
All XOR operations run locally in your browser. Your plaintext, ciphertext, and key never leave your device, ensuring 100% privacy every time you use our XOR cipher tool online.
XOR Cipher Online - No Installation
Use our XOR cipher tool directly in any browser with no downloads, plugins, or software required. Encrypt and decrypt text using XOR from any device, anywhere, completely free.
Multiple Formats + Visual XOR Table
Supports UTF-8, hexadecimal, and Base64 for both input and key. The visual XOR operation table shows the byte-by-byte XOR calculation for the first 16 bytes, making it ideal for learning and debugging.
Common Use Cases for XOR Cipher Tool
Cryptography Education & Learning
Students and educators use our XOR cipher tool to learn the fundamentals of symmetric encryption, bitwise operations, and the one-time pad. The visual XOR table shows the byte-by-byte operation for hands-on understanding.
CTF (Capture the Flag) Challenges
Security researchers and CTF participants use our XOR cipher tool to quickly encrypt and decrypt XOR-encoded challenges. Supports hex and Base64 input formats commonly used in CTF flag encoding.
Simple Data Obfuscation
Developers use XOR encryption to lightly obfuscate configuration values, license keys, and embedded strings in applications. While not cryptographically secure for sensitive data, XOR obfuscation deters casual inspection.
Network Protocol Analysis
Network engineers and security analysts use our XOR cipher tool to decode XOR-obfuscated payloads found in network traffic captures. Enter the hex payload and known key to recover the plaintext instantly.
Malware Analysis & Reverse Engineering
Security researchers use XOR decryption to decode XOR-obfuscated strings in malware samples. Our tool supports hex key input and hex output, matching the format used in most XOR-encoded malware payloads.
One-Time Pad Demonstrations
Cryptography instructors use our XOR cipher tool to demonstrate the one-time pad - the only theoretically unbreakable cipher. When the key is as long as the message and used only once, XOR provides perfect secrecy.
Understanding the XOR Cipher
What is the XOR Cipher?
The XOR cipher is a symmetric encryption technique that applies the bitwise XOR (exclusive OR) operation between each byte of the plaintext and the corresponding byte of a key. The XOR operation produces a 1 when the two input bits differ and a 0 when they are the same - making it perfectly reversible with the same key. Our XOR cipher tool supports UTF-8, hexadecimal, and Base64 input and key formats, making it suitable for a wide range of use cases from CTF challenges to malware analysis. The tool also displays a visual XOR operation table showing the byte-by-byte calculation for the first 16 bytes, making it ideal for learning and debugging. All processing runs locally in your browser with no data sent to any server.
How Our XOR Cipher Tool Works
- 1. Enter Your Input and Key: Select the input format (UTF-8, hex, or Base64), enter your text, then select the key format and enter your key. For decryption, use the same key and swap the input/output formats.
- 2. Instant Browser-Based XOR Processing: Click Apply XOR and the tool instantly XORs each byte of the input with the corresponding byte of the key (cycling the key if it is shorter than the input). All processing happens locally in your browser.
- 3. Copy or Download the Output: The XOR result appears in the output panel in your chosen format (hex, Base64, or UTF-8). Copy it with one click or download it as a text file. The visual XOR table shows the byte-by-byte operation.
XOR Cipher Properties
- Symmetric Operation: XOR is its own inverse: A ⊕ B = C, and C ⊕ B = A. This means the same key and operation is used for both encryption and decryption. To decrypt, simply apply XOR again with the same key.
- Repeating Key (Vigenère-style): When the key is shorter than the input, it repeats cyclically. For example, with a 3-byte key "ABC" and a 9-byte input, the key pattern is "ABCABCABC". This is the standard XOR cipher mode used in most applications.
- One-Time Pad (Perfect Secrecy): When the key is exactly as long as the input and is used only once (never reused), XOR becomes the one-time pad - the only cipher with proven perfect secrecy. Every possible plaintext is equally likely given the ciphertext.
- Security Limitations: XOR with a short repeating key is not cryptographically secure for sensitive data. If an attacker knows part of the plaintext, they can recover the key. For secure encryption, use AES-256-GCM instead. XOR is best used for obfuscation, CTF challenges, and educational purposes.
XOR Truth Table
| A | B | A ⊕ B |
|---|---|---|
| 0 | 0 | 0 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 0 |
XOR outputs 1 only when the inputs differ. This property makes it perfectly reversible: applying XOR twice with the same key always recovers the original value.
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Frequently Asked Questions About XOR Cipher Tool
A XOR cipher tool applies the bitwise XOR (exclusive OR) operation between each byte of the input and the corresponding byte of a key. Our XOR cipher tool supports UTF-8, hex, and Base64 formats for both input and key, and displays a visual byte-by-byte XOR table. All processing runs locally in your browser.
XOR is symmetric - to decrypt, apply XOR again with the same key. Enter the ciphertext (in hex or Base64 format), enter the same key used for encryption, and click Apply XOR. The output will be the original plaintext.
Our XOR cipher tool supports three key formats: UTF-8 text (e.g. "secret"), hexadecimal (e.g. "DEADBEEF" or "0xDE 0xAD"), and Base64 (e.g. "3q2+7w=="). Choose the format that matches your key and the tool handles the conversion automatically.
When the key is shorter than the input, it repeats cyclically. For example, a 3-byte key "ABC" applied to a 9-byte input uses the pattern "ABCABCABC". This is the standard repeating-key XOR cipher, also known as a Vigenère-style XOR.
XOR with a short repeating key is not cryptographically secure for sensitive data. If an attacker knows part of the plaintext, they can recover the key. For secure encryption, use AES-256-GCM instead. XOR is best used for obfuscation, CTF challenges, educational purposes, and one-time pad demonstrations.
A one-time pad is a XOR cipher where the key is exactly as long as the message and is used only once. When these conditions are met, XOR provides perfect secrecy - every possible plaintext is equally likely given the ciphertext, making it theoretically unbreakable. Our XOR cipher tool supports this mode when you provide a key of the same length as the input.
Yes! Our XOR cipher tool is 100% free with no signup, no ads, and no usage limits. Encrypt and decrypt text using XOR as many times as you need - completely free, forever.
Absolutely. All XOR operations happen locally in your browser using JavaScript. Your plaintext, ciphertext, and key are never sent to any server. Once you close the page, nothing is retained - there are no logs, no storage, and no telemetry.
The XOR operation table shows the byte-by-byte XOR calculation for the first 16 bytes of your input. Each row shows the input byte (hex), the key byte (hex), the XOR result (hex), and the full binary representation of the operation. This is useful for learning, debugging, and verifying XOR implementations.