LogisimRevisited

Learn

Logisim Online in Your Browser (No Java Required)

Run Logisim online directly in your web browser without installing Java: open and export .circ files, simulate 4-state digital logic, and debug circuits with the Logisim AI Coach.

Run Logisim Online Without Installing Java

Classic Logisim 2.7.1 is a desktop Java (.jar) application. Modern school laptops, Chromebooks, iPads, and work computers often block Java installations or struggle with High-DPI scaling on legacy Swing windows.

Logisim Revisited lets you run Logisim online directly in your browser. The discrete-event 4-state simulation engine, schematic editor, and .circ XML parser are rebuilt in pure TypeScript—so there is nothing to download, no Java Runtime Environment (JRE) required, and your circuits never leave your device.

Opening and Saving Your .circ Files Online

  1. Open the online Logisim simulator in any desktop, Chromebook, or mobile browser.
  2. Click Import in the top toolbar and choose your existing Logisim 2.7.1 .circ file.
  3. Use the Poke tool to toggle Input Pins, step the Clock, and inspect wires live.
  4. Click Export at any time to download a standard .circ XML file that opens back in desktop Logisim 2.7.1.

All 41 core components across the six classic libraries—Wiring (Pin, Tunnel, Splitter, Clock), Gates (XOR, NAND, Tri-State Buffer), Plexers (MUX, Decoder), Arithmetic (Adder, Comparator), Memory (S-R Flip-Flop, T Flip-Flop, J-K Flip-Flop, D Flip-Flop, Register, Counter, ROM), and Input/Output (7-Segment Display, Hex Digit Display)—are simulated right in the browser. See the full component reference.

What Logisim Revisited Adds Beyond Logisim 2.7.1

  • Logisim AI Circuit Coach & Signal Prover: Ask "Why is this wire 0, 1, E, or Z?" on any pin or net to trace its upstream drivers step by step, or get 4-stage Socratic hints without spoiling the answer.
  • Karnaugh Map & Quine-McCluskey Analyzer: Enter a truth table or Boolean expression, view the Gray-code K-map loops, and synthesize a two-level gate circuit onto the canvas in one click.
  • Daily Logic Challenges: Practice building and debugging combinational and sequential circuits with a new graded puzzle every day.