Logic Gate Simulator
Simulate AND, OR, NOT, NAND, NOR, XOR, XNOR, and BUFFER logic gates with our free logic gate simulator. Toggle binary inputs between 0 and 1 and see the output update instantly — with the full truth table and Boolean expression for every gate. Add up to 8 gates simultaneously and explore chained circuit behaviour. All simulations run locally in your browser with no signup required.
Select a gate type (AND, OR, NOT, NAND, NOR, XOR, XNOR, BUFFER), toggle the input values between 0 and 1, and see the output update instantly. Each gate shows its truth table and the Boolean expression for your current inputs — all running locally in your browser.
Output is 1 only when ALL inputs are 1
A AND B = 1 AND 1 = 1
| A | B | Output |
|---|---|---|
| 0 | 0 | 0 |
| 0 | 1 | 0 |
| 1 | 0 | 0 |
| 1 | 1 | 1 |
Output is 1 when ANY input is 1
A OR B = 1 OR 0 = 1
| A | B | Output |
|---|---|---|
| 0 | 0 | 0 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 1 |
Output is the inverse of the input
NOT A = NOT 1 = 0
| A | Output |
|---|---|
| 0 | 1 |
| 1 | 0 |
Expression: (NOT A) AND B OR C = (NOT 1) AND 0 OR 1 = 1
Why Use Our Logic Gate Simulator?
Accurate, interactive, and fully browser-based digital logic simulation
Instant Logic Gate Simulation
Toggle input values between 0 and 1 and see the gate output update in real time — no delay, no page reload. Our logic gate simulator evaluates AND, OR, NOT, NAND, NOR, XOR, XNOR, and BUFFER gates instantly with the correct Boolean logic for every input combination.
Secure Logic Gate Simulator Online
All logic gate simulations run locally in your browser using JavaScript. Your circuit configurations and input values are never sent to any server — the logic gate simulator processes everything on your device with complete privacy.
Logic Gate Simulator - No Installation
Use the logic gate simulator directly in any modern browser with no downloads, plugins, or sign-up required. Add up to 8 gates simultaneously, chain them together, and view truth tables for every gate type — all without installing any software.
100% Free with No Limits
The logic gate simulator is completely free with no signup, no usage limits, and no ads. Simulate any combination of AND, OR, NOT, NAND, NOR, XOR, XNOR, and BUFFER gates, view full truth tables, and explore chained circuit behaviour — all free forever.
Common Use Cases for Logic Gate Simulator
Practical applications for digital logic gate simulation
Computer Science & Digital Electronics Coursework
Students use the logic gate simulator to verify homework answers and understand how AND, OR, NOT, NAND, NOR, XOR, and XNOR gates behave with different inputs. The truth table for each gate makes it easy to check your work against textbook answers.
Boolean Algebra Practice
Use the logic gate simulator to test Boolean expressions by mapping them to gate combinations. Toggle inputs between 0 and 1 to verify that your Boolean simplification produces the same output as the original expression.
Circuit Design Prototyping
Electronics engineers use the logic gate simulator to quickly prototype and verify small combinational logic circuits before implementing them in hardware or HDL. The chained circuit panel demonstrates how gate outputs feed into subsequent gates.
Teaching Digital Logic Concepts
Teachers use the logic gate simulator to demonstrate logic gate behaviour in real time during lectures. The visual output indicator (green for 1, red for 0) makes it immediately clear how each gate responds to different input combinations.
FPGA and HDL Development
FPGA developers and VHDL/Verilog learners use the logic gate simulator to verify the expected behaviour of individual gate primitives before writing HDL code. Understanding gate-level behaviour is essential for correct hardware description.
Competitive Programming & Logic Puzzles
Competitive programmers use the logic gate simulator to quickly check bitwise operation results and understand XOR, NAND, and NOR behaviour for algorithm design. The truth tables provide an instant reference for all gate types.
Understanding Logic Gate Simulation
How logic gates work and what each gate type does
What is a Logic Gate Simulator?
A logic gate simulator is a tool that models the behaviour of digital logic gates — the fundamental building blocks of all digital circuits and computers. Each logic gate takes one or two binary inputs (0 or 1) and produces a single binary output according to a fixed Boolean function. Our logic gate simulator supports all seven standard gate types: AND, OR, NOT, NAND, NOR, XOR, and XNOR, plus the BUFFER gate. For each gate, the simulator shows the current output for your selected inputs, the full truth table for all possible input combinations, and the Boolean expression — all updating instantly as you toggle inputs.
How Our Logic Gate Simulator Works
- Select a Gate Type: Click any gate type button (AND, OR, NOT, NAND, NOR, XOR, XNOR, BUFFER) to set the gate for that row. You can add up to 8 gates simultaneously to compare different gate behaviours side by side.
- Toggle Input Values: Click the A and B input buttons to toggle between 0 and 1. The output updates instantly — green for logic 1 (HIGH) and red for logic 0 (LOW). Single-input gates (NOT, BUFFER) only use input A.
- Read the Truth Table and Expression: Each gate row shows the complete truth table for all possible input combinations and the Boolean expression for your current inputs. Use the chained circuit panel to see how gate outputs feed into subsequent gates in a multi-gate circuit.
What Each Logic Gate Does
- AND: Output is 1 only when both inputs A and B are 1. Used for conditions that require all criteria to be true simultaneously.
- OR: Output is 1 when at least one input is 1. Used for conditions where any one of multiple criteria being true is sufficient.
- NOT: Output is the inverse of input A — 0 becomes 1 and 1 becomes 0. Used to invert signals and implement logical negation.
- NAND: Output is 0 only when both inputs are 1 (NOT AND). NAND is a universal gate — any Boolean function can be built from NAND gates alone.
- NOR: Output is 1 only when both inputs are 0 (NOT OR). NOR is also a universal gate and is used extensively in CMOS circuit design.
- XOR: Output is 1 when inputs are different (exclusive OR). Used in adder circuits, parity checkers, and cryptographic operations.
- XNOR: Output is 1 when inputs are the same (NOT XOR). Used in equality comparators and error detection circuits.
Important Notes About the Logic Gate Simulator
The logic gate simulator models combinational logic — circuits where the output depends only on the current inputs, with no memory or feedback. Sequential logic (flip-flops, registers, counters) and tri-state logic are not modelled. The simulator uses standard positive logic convention where 1 represents HIGH voltage and 0 represents LOW voltage. All gate evaluations use exact Boolean arithmetic — there is no propagation delay, noise, or analogue behaviour modelled. For hardware implementation, always verify your circuit design with a proper EDA tool (e.g. Logisim, KiCad, or Quartus).
Frequently Asked Questions About Logic Gate Simulator
Common questions about logic gates and how the simulator works
A logic gate simulator is a tool that models the behaviour of digital logic gates — AND, OR, NOT, NAND, NOR, XOR, XNOR, and BUFFER. You select a gate type, toggle the binary inputs (0 or 1), and the simulator instantly shows the output, the Boolean expression, and the full truth table for all possible input combinations. Our logic gate simulator runs entirely in your browser with no signup required.
The logic gate simulator supports all seven standard gate types: AND (output 1 when all inputs are 1), OR (output 1 when any input is 1), NOT (inverts the input), NAND (NOT AND), NOR (NOT OR), XOR (output 1 when inputs differ), and XNOR (output 1 when inputs are the same). It also supports the BUFFER gate, which passes the input through unchanged.
Click a gate type button (AND, OR, NOT, etc.) to select the gate for a row. Then click the A and B input buttons to toggle between 0 and 1. The output updates instantly — green for logic 1 and red for logic 0. You can add up to 8 gates simultaneously and use the chained circuit panel to see how gates connect in series.
An AND gate outputs 1 only when both inputs are 1. A NAND gate (NOT AND) outputs the opposite — it outputs 0 only when both inputs are 1, and 1 in all other cases. NAND is a universal gate, meaning any Boolean function can be implemented using only NAND gates. This makes NAND gates extremely important in digital circuit design.
Yes! Our logic gate simulator is 100% free with no signup, no account, and no usage limits. Simulate any combination of logic gates, view truth tables, and explore chained circuits — completely free, forever.
An XOR (exclusive OR) gate outputs 1 when the inputs are different (one is 0 and the other is 1). An XNOR gate (NOT XOR) outputs 1 when the inputs are the same (both 0 or both 1). XOR is used in adder circuits and parity checkers; XNOR is used in equality comparators.
Absolutely. All logic gate simulations run entirely in your browser using JavaScript. Your circuit configurations and input values are never transmitted to any server. Your data stays completely private on your device every time you use our logic gate simulator online.
Yes. The chained circuit panel demonstrates a three-gate chain: NOT → AND → OR. You can toggle all three inputs (A, B, C) and see how the output of each gate feeds into the next. This illustrates how combinational logic circuits are built from individual gate primitives.
A universal gate is a gate from which any other Boolean function can be constructed using only that gate type. NAND and NOR are both universal gates. This matters in hardware design because it means an entire digital circuit can be built using only one type of gate, simplifying manufacturing and reducing the number of distinct components needed.