A daily logic-gate puzzle
Circuitle is a browser puzzle about digital logic. Each day it
generates one truth table, a small boolean function of three
inputs, and asks you to build a circuit that matches every row.
You wire logic gates (AND, OR, NOT, XOR, NAND, NOR, XNOR) from the
inputs to a single output, and the board simulates your circuit
live against the target. The catch is efficiency: any working
circuit solves the puzzle, but your score is the number of gates
you used, measured against par, the smallest number of gates the
function actually needs. Getting a solution is the warm-up.
Getting the minimal one is the game.
How to play
Read the day's target truth table, drag gates onto the board (or
place them from the keyboard), and connect pins by clicking a
source pin then a target pin. Rows turn green as your circuit
starts matching them. When every row passes you win, and Circuitle
shows your gate count next to par along with a share line you can
copy. The same puzzle appears for everyone on a given UTC date, so
a score is worth comparing. Nothing is stored on a server; your
best gate count per day lives in your browser.
FAQ
- Do I need to know electronics to play?
-
Basic familiarity with logic gates helps, but the truth table
tells you exactly what each combination of inputs should
produce, so you can reason it out from the table alone. If you
know that AND is true only when both inputs are true, you know
enough to start.
- What is par, and how is it calculated?
-
Par is the fewest gates any circuit could use to reproduce that
day's truth table. Circuitle computes it with a shortest-path
search over the function's possible sub-signals, so it is a real
lower bound, not an estimate. Beating par means you found a
smaller circuit than the reference solution.
- Is the puzzle the same for everyone?
-
Yes. The day's truth table is seeded from the UTC date, so every
player on the same day faces the identical function. That is what
makes sharing a gate count meaningful.
- Can I play with only the keyboard?
-
Yes. Placing a gate, wiring two pins, and deleting a gate all
have keyboard equivalents, and the board announces the pin you
are on for screen readers.
- Does it work on my phone?
-
Yes. The board resizes to your screen and gates are drag-and-drop
on touch, with the truth table and gate dock laid out for narrow
widths.