Logic Friday alternative: minimize logic in your browser
Logic Friday is a free Windows program for combinational logic design. As Wikipedia describes it, it is a graphical interface to Espresso, the Berkeley heuristic logic minimizer, and to misII, another module of the Berkeley Octtools package: you enter a function as a truth table, an equation or a gate diagram, minimize it, and see the result in the other two forms. Its last release was version 1.1.4, dated 2012, and its listed home page, sontrak.com, did not load when we checked. If you are looking for the same job done in a browser on any computer, digiwleea's free tools cover each step.
What Logic Friday is good at
It puts a serious minimizer behind a simple window. Espresso handles functions far too large for Karnaugh maps, and Logic Friday's three linked views (truth table, equation, gates) make it easy to check a design from every side. Because it runs offline on Windows, it also works without an internet connection. (digiwleea is an independent project, not affiliated with Logic Friday or its author.)
How digiwleea's tools compare
digiwleea's tools run in any browser, phones included, with nothing to install. The truth table to expression converter gives minterms, maxterms and the minimal SOP and POS, with don't cares; the Boolean simplifier reduces an expression of up to 8 variables; the Karnaugh map solver shows the groups for 2 to 6 variables; and the logic circuit generator turns an expression into a working gate circuit, checked on every row. They are exact but sized for teaching: for very large functions, Espresso itself (or a synthesis tool) is the better choice. Behind the tools sits a course that builds those gates from CMOS transistors up to an 8-bit CPU.
| Logic Friday | digiwleea | |
|---|---|---|
| Runs on | Windows (last release 2012) | Any modern browser, phones included |
| Enter a function as | Truth table, equation or gate diagram | Expression, truth table (with don't cares) or K-map |
| Minimizer | Espresso and misII | Exact minimal forms: SOP and POS from a truth table of up to 6 variables, SOP from an expression of up to 8 |
| Gate output | Multi-level gate diagram | A working circuit, checked on every row, that opens in the lab |
| Price | Free | Free tools; free lab and Act I |
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.
More comparisons: Logic simulators
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 Logic Friday still available?
Its last release was version 1.1.4 in 2012, according to Wikipedia, and its listed home page, sontrak.com, did not load when we checked on 2026-10-29. Browser tools such as digiwleea's need no download.
What does Logic Friday do?
It is a free Windows front end to the Espresso logic minimizer and to misII. You enter a function as a truth table, an equation or a gate diagram, minimize it, and see the result in the other two forms.
Is there an online alternative to Logic Friday?
Yes. digiwleea's free browser tools convert a truth table to its minimal SOP and POS, simplify Boolean expressions of up to 8 variables, solve Karnaugh maps of 2 to 6 variables, and turn an expression into a working circuit.
What is the Espresso algorithm?
A heuristic two-level logic minimizer from the 1980s, begun at IBM and developed further at UC Berkeley. It finds a near-minimal sum of products quickly, even for functions with many inputs where exact methods such as Quine-McCluskey become too slow.