Alibi

A logic grid puzzle gives you a set of suspects and several attribute categories — in Alibi: location, carried item, and arrival time. Clue statements relate these categories to each other. You use the grid to record what you know: a check means this suspect has this attribute, a cross means they do not. When one cell gets a check, every other cell in that row and column automatically gets a cross.

Click or tap a cell once to place a check (confirmed match). Click again to place a cross (confirmed non-match). Click a third time to clear the cell. Right-click or long-press sets a cell directly to cross for fast elimination. When you confirm a match, Alibi automatically marks the rest of that row and column as non-matches.

Each suspect has exactly one value for each attribute. When you check one cell, Alibi fills in all the other cells in that row and column as crosses. This cascading effect can unlock several cells at once, turning one confident deduction into many.

Easy cases use 4 suspects and 3 attribute categories. Medium uses 5 suspects. Hard uses 6 suspects and 4 attribute categories. Difficulty cycles by day of the week: Easy on Mondays, Medium Tuesday through Thursday, Hard on Fridays, Saturdays, and Sundays.

Tap the date in the top bar to open the archive date picker. Past cases are freely accessible — solved cases display the clue-efficiency score you achieved. Unsolved past cases can be attempted at any time without affecting your current streak.

The clue efficiency score is the total number of clues in the case minus the number you needed to read before solving. A lower clue count means a more efficient solve. Three stars if you solved using only the first half of the clues; two stars for any other completion using all clues; one star for completing regardless.

Re-read every clue carefully — logic-grid clues often contain two constraints in one sentence. If every mark looks consistent but no new cell is obvious, try reading clues that mention two attributes you have not connected yet. All cases are designed so no guessing is ever required — a deduction path exists for every cell.

Tap a cell to toggle through unknown, check, and cross. Long-press a cell to set it directly to cross for fast elimination. On small screens the clue panel stacks above the grid. All cells are at least 40x40 pixels for comfortable tapping.

Yes. Your progress on the current daily case, your solve history, and your streak counter are all saved in your browser's localStorage. Progress persists across page reloads. Clearing your browser data will reset saved progress — there is no server-side account required.

Each day's case is generated using the ISO date string as a seed. The same seed always produces the same case, so every player worldwide gets an identical puzzle on the same calendar day. This makes it fair to compare clue-efficiency scores with others.

Yes. Press R on the keyboard or use the reset option in the menu to clear all marks and start the case over. A confirmation dialog prevents accidental resets. Resetting does not affect your streak — only solving counts toward streaks.

R resets the current case (with confirmation). Escape deselects any highlighted clue and closes overlays. On desktop, right-clicking a cell sets it directly to cross for quick elimination. All other interactions are click or tap based.