Logisim, but online in your browser (no Java, no install)
Logisim (and its maintained fork logisim-evolution) is the classic free logic simulator used in countless university digital-logic courses: you drag pre-built gates and subcircuits onto a canvas. It runs as a Java desktop app you download and install. If that is what brought you here, digiwleea is a free, in-browser alternative with a different angle: you build a computer from the transistor up.
What Logisim is good at
Logisim is a proven, capable classroom tool with a rich component library and hierarchical subcircuits, and if your course standardizes on it you will feel right at home.
How digiwleea is different
digiwleea runs entirely in the browser with nothing to install (no Java runtime), and it teaches from a deeper layer: instead of starting at pre-built gates, you build the gates themselves from CMOS transistors and the simulator verifies them against the real truth table. From there a guided 30+ level course and a gamified "sand to CPU" journey carry you up to a working 8-bit processor, with an AI tutor (Wleea) alongside. It is less a blank canvas and more a guided path to understanding the machine, though you can still free-build any circuit you like.
| Logisim | digiwleea | |
|---|---|---|
| Runs in | Java desktop app (download) | The browser, nothing to install |
| Smallest building block | Pre-built gates | CMOS transistors (build the gates too) |
| Guided course to a CPU | No (open sandbox) | Yes, 30+ levels |
| Live truth-table check | Manual test vectors | Instant, built in |
| AI tutor | No | Yes (Wleea) |
No sign-up is needed to start: open the lab and place your first transistor, or read the free theory course. The account (and the AI tutor) are optional.
See for yourself: build a logic gate from transistors in the simulator, then follow the path from sand to an 8-bit CPU.
Open the digiwleea lab →Frequently asked
Is digiwleea a good Logisim alternative?
Yes, if you want to understand digital logic from the ground up. digiwleea is a free, in-browser simulator and 30+ level course where you build every gate from CMOS transistors and work up to a real 8-bit CPU, with an AI tutor to help.
Is digiwleea free?
The sandbox lab and the first act of the course are free and need no sign-up. An optional account adds the AI tutor and cross-device sync; the full course and tutor are a one-time unlock plus an optional subscription.
Do I need to install anything?
No. digiwleea runs entirely in your browser, on desktop or mobile, and works offline once loaded.