Lights Out daily boards, exact par, zero guesswork
Press one light to flip it and its orthogonal neighbors. Daily opens first; every board is guaranteed solvable and the exact minimum is recalculated from your current state. Practice scales from 3×3 through 7×7.
Classic 5×5 · exact minimum —
Turn every light off.
Lights out
—
More · archive, Practice, solver & local record
Daily archive
Every date has deterministic Quick 4×4, Classic 5×5 and Challenge 6×6 boards.
Practice
Exact solver
The current board is solved locally by first-row enumeration and row chasing. No upload or API.
Display & portability
All progress stays in this browser. Exact links reproduce Daily date or Practice size, difficulty and seed.
Local record
Minimum, not an estimate
The solver checks every possible first-row press pattern and reports the shortest successful set.
Par left updates
After every press, the current board is solved again so you can see the exact remaining distance.
Three useful sizes
Quick 4×4, Classic 5×5 and Challenge 6×6 share one date-stable Daily set and local streak.
3×3 through 7×7
Choose size and difficulty, then replay the exact same seeded puzzle from a copied link.
Advanced · V0.209 exact evidence, fixed benchmark & manual 3×3–5×5 solver
Exact Solver & Repeatability Lab
Use the same toggle engine that powers the game to inspect exact distance, review completed solves, enter an arbitrary board, and repeat fixed boards against your own prior runs. These are task-local measurements only—no IQ, diagnostic or population score.
Make a press in the base puzzle.
Exact remaining-distance evidence will appear here.
Opening shortest sets marks the active base run Assisted so personal-best evidence stays honest.
No completed solve review yet.
Finish the base puzzle to retain exact local evidence.
Five-board repeatability benchmark
Fixed A–E uses one Easy, one Standard, two Classic and one Target Pattern board. Complete all five clean boards once each; repeating only one board never unlocks Clean-5.
Enter any abstract board
Choose 3×3, 4×4 or 5×5, toggle the starting cells, then solve toward all-off or the target pattern. The solver reports no-solution honestly, or shows every shortest press-set found by first-row enumeration.
Local JSON backup
Export/import Lights Out base stats plus the V0.209 review/benchmark lab. No account or server is required.
Practice settings
Exact minimum and solver results come from the local toggle engine. Personal repeatability numbers describe only your own runs in this browser; they are not cognitive or medical norms.