Digital Logic Simulator
Learn and experiment with digital electronics right in the browser: drag logic gates onto the board, wire them together, toggle inputs between 0 and 1 and watch the signals propagate in real time — green wires mean logic level 1. With feedback support, even circuits with memory, like the SR latch, genuinely work. Ready-made examples are included to start studying.
Tap a part to add it. Drag to position. Click an output dot then an input dot to wire them. Click an Input to toggle 0/1.
Your circuit is saved in the browser automatically.
All the classic gates
AND, OR, NOT, NAND, NOR, XOR and XNOR, plus toggleable inputs, outputs with a light indicator and a clock that ticks on its own — useful for watching circuits in motion. Every part shows its live state, and wires change color with the signal.
Circuits with memory actually work
Unlike simple simulators that only compute left to right, this one propagates signals in successive sweeps until the circuit settles. That allows feedback — cross-couple two NOR gates and you have an SR latch storing one bit, exactly like in real electronics.
Ready-made examples to study
Load with one click the half adder (the basis of binary arithmetic), the SR latch (the simplest memory circuit) and XOR built only from NANDs (an exam classic). Then modify freely — your circuit is saved automatically in the browser.
How to use
Tap a part in the palette to add it to the board and drag to position it. To run a wire, click the output dot of one part and then the input dot of another. Click an Input to toggle between 0 and 1. Select a part or wire and use "Delete" to remove it. On mobile, the board scrolls horizontally.
Frequently asked questions
Does it work on mobile?
Yes. Adding, dragging, wiring and toggling inputs all work by touch, and the board scrolls horizontally for larger circuits.
Is my circuit saved?
Yes, automatically in your browser. When you come back it will be exactly as you left it.
Why does the SR latch work here?
Because the simulation propagates signals in successive sweeps until it settles, instead of computing in a single pass — which allows feedback between gates, essential for memory circuits.
Is it useful for exam prep?
Yes. It's a visual way to verify truth tables, test boolean identities and understand classic circuits like adders and latches.