The XNOR gate is a digital logic gate whose function is the logical complement of the exclusive OR (XOR) gate. The two-input version implements logical equality, behaving according to the truth table below. A high output (1) results if both of the inputs to the gate are the same. If one but not both inputs are high (1), a low output (0) results.

INPUT OUTPUT
A B A XNOR B (Q)
0 0 1
0 1 0
1 0 0
1 1 1

Truth Table

MIL/ANSI Symbol