Logic Grid

Logic Grid is a logic gate simulator. It features common logic gates such as AND, XOR, flip-flops, and others. It also simulates a simple microprocessor called FLEX. It is written in JavaScript and uses HTML5 features to draw its editor.

Start Logic Grid


Drag and drop the gate of choice onto the canvas and connect it with other gates by drawing wires. For more information on how to use Logic Grid, please read the Help text in the editor. You can also try to load one of the provided examples.

FLEX Microprocessor

The FLEX is a microprocessor used at a course on Chalmers. In Logic Grid it is used as any other logic gate; simply place it and program it using the built-in text editor and assembler.

For more information, see the instruction set (Swedish) and read the Help text in the editor. There is also an example circuit containing a simple counter built using a FLEX.


A complex circuit is built by connecting smaller parts into components. For instance, an 8-bit full adder can be created using eight 1-bit full adders. This concept can be used in Logic Grid as it supports the creation of reusable components.

To create a reusable component, simply create a circuit, place and name outputs and inputs, then save it and give it a useful name. Create a new grid. Hit load and click "Add as gate" on the newly save circuit to use it as a gate (component).