Light Bulbs
Light Bulbs — known as Akari or 美術館 — is a calm logic puzzle of illumination. Place light bulbs on the white cells of a grid so every white cell is lit, while no bulb shines onto another and every numbered wall has exactly that many bulbs beside it. Every hand-authored, solver-verified puzzle has a single solution you can deduce without guessing.
How to play
- Tap a white cell to cycle it through bulb, a marker dot, and empty.
- Each bulb lights its full row and column until a black wall blocks the beam.
- Make sure no bulb shines directly onto another bulb — beams must never meet.
- Give every numbered wall exactly that many bulbs among its four orthogonal neighbours.
- Light every white cell to solve the puzzle, or use the hint to reveal one correct bulb.
Tips
- Start at the numbered walls — a 0 means no bulbs touch it, and a high number often forces bulbs outright.
- Use the dot marker on cells you have proven empty; it keeps your deductions visible and prevents mistakes.
- A wall turns red when its number can no longer be met — back up and rethink the bulbs around it.
FAQ
- Is Light Bulbs free to play?
- Yes. Light Bulbs runs free in your browser with no installs, sign-up, or downloads, on both desktop and mobile.
- How do you win Light Bulbs?
- You solve a puzzle when every white cell is lit, no two bulbs shine on each other, and every numbered wall has its exact bulb count.
- What is the difference between Akari and Light Bulbs?
- They are the same puzzle. Akari, also called 美術館, is the Japanese name for this light-placement logic genre.
- Does Light Bulbs work on mobile?
- Yes. The grid is touch-friendly — tap to cycle a cell — and scales to phone and tablet screens.