XOR is a logical operator whose negation is the logical biconditional.
XOR may also refer to:
- XOR cipher, an encryption algorithm
- XOR gate, a digital logic gate
- bitwise XOR, an operator used in computer programming
- XOR (video game), a 1987 puzzle video game
- XOR, an x200 instruction
- Xor DDoS, a Linux Trojan malware
- XOR Corporation, a video game publisher and developer
- XOR, a character from Ultimate Custom Night