Master Digital Logic
One Circuit at a Time
An interactive circuit simulator built for engineering students. Toggle switches, watch signals flow through gates in real time, see LEDs light up, and study truth tables — all in your browser. No setup required.
Learn by Doing
Pick a Lab
Browse 18 labs across 7 categories — from basic gates to sequential flip-flops.
Toggle Inputs
Click switches to flip inputs between 0 and 1. Every change propagates instantly.
Watch Signals Flow
Wires glow and animate when carrying HIGH. LEDs light up with color-coded outputs.
Study the Table
The truth table auto-highlights the row matching your current input combination.
All 18 Labs
No sign-up required. Every lab runs entirely in your browser.
The simplest bistable element with Set and Reset inputs.
Data flip-flop that captures input on each rising clock edge.
Versatile flip-flop eliminating the invalid state of SR design.
Cascaded master-slave configuration eliminating the race-around condition.
Md. Mehedi Hasan
EEE Graduate · Programming Enthusiast
Electrical & Electronic Engineering graduate who loves programming as a hobby. Built this DLD simulator to make digital logic concepts interactive and easy to understand — every circuit runs on real boolean logic, no shortcuts.