Frequently Asked Questions
Everything you need to know about the Logic Gate Simulator.
What are logic gates?
Logic gates are the basic building blocks of digital circuits. Each takes one or more binary inputs (0 or 1) and produces a single binary output based on a fixed rule.
What does an AND gate do?
An AND gate outputs 1 only when both inputs are 1. If either input is 0, the output is 0.
What does an OR gate do?
An OR gate outputs 1 when at least one input is 1. It only outputs 0 when both inputs are 0.
What is a NOT gate?
A NOT gate, or inverter, takes a single input and flips it — 0 becomes 1, and 1 becomes 0.
What's the difference between NAND/NOR and AND/OR?
NAND is AND followed by NOT, and NOR is OR followed by NOT — both simply invert the corresponding gate's output.
What does XOR mean?
XOR (exclusive OR) outputs 1 when the two inputs differ, and 0 when they're the same.
What is XNOR?
XNOR is the inverse of XOR — it outputs 1 when the two inputs match, and 0 when they differ.
Why are NAND and NOR called universal gates?
Any logic function — AND, OR, NOT, or any combination — can be built using only NAND gates, or only NOR gates, which makes them 'universal' for circuit design.
How do I read the truth table?
Each row lists one combination of inputs and the resulting output for the selected gate. The row matching your current toggle settings is highlighted.
Is this simulator free to use?
Yes, completely free with no sign-up, and it runs entirely in your browser.