How to solve Akari
Light every cell with bulbs
Akari — also called Light Up, or 美術館 (Bijutsukan) by Japan's Nikoli — has you place light bulbs so every white cell is lit, while no two bulbs shine on each other and each numbered wall touches exactly that many bulbs. A beloved Japanese classic that few sites offer unlimited: play free Akari boards here, every one with a single solution.
How to play Akari
- Place light bulbs on white cells so that every white cell is lit.
- A bulb lights its whole row and column until a black cell blocks the light — but two bulbs may never shine on each other.
- A number on a black cell says exactly how many bulbs touch it horizontally and vertically.
- Black cells without a number are plain walls — they don't constrain anything.
- Tap a cell to place a bulb, again for a dot (no bulb here), once more to clear.
How to solve Akari: techniques that work
Open every board with the extreme clues. A wall numbered 4 lights bulbs on all four sides; a 0 forbids bulbs on all its neighbours — mark those cells with dots at once. A 3-wall in the open, or a 2-wall in a corner, is fully forced too. These free moves light a surprising share of the grid before any real thinking starts.
Then hunt for cells that only they themselves can light. A white cell whose row and column segments are otherwise dotted out or blocked by walls must hold a bulb — no other bulb can ever reach it. This "self-light" argument is the workhorse of midgame Akari.
Dots are half the game. Every cell a bulb shines on is dotted by the app automatically through its light ray, but add your own dots wherever a bulb would break a satisfied wall clue or stare down an existing bulb. The more dots you place, the more self-light cells appear.
Common mistakes
Placing two bulbs in the same corridor: bulbs must never shine on each other, and a single long row with two bulbs and no wall between them invalidates the board even if everything is lit.
Treating unnumbered walls as clues. Black cells without a number impose nothing — they only block light. Their job is to cut long corridors into short segments.
From easy to hard
On easy boards every wall is numbered, so clue-chaining carries you through. Medium and hard boards leave walls blank and stretch the corridors: expect to lean on the self-light argument and on careful dotting. Akari is Nikoli's Light Up (美術館) — one of the most elegant deduction puzzles ever designed.
FAQ
- Is Akari free and unlimited on LinkMyPzzl?
- Yes. Every Akari board is generated on demand in your browser — play as many as you want, for free, with no account.
- How is this different from the daily Akari puzzle?
- The daily version made popular by LinkedIn offers one grid per day. LinkMyPzzl generates unlimited boards and lets you choose the difficulty, so you can actually train.
- Does every Akari board have a unique solution?
- Yes. A solver verifies every generated board before you see it: there is always exactly one solution.
- What are the black cells without numbers?
- Plain walls. They block light and split rows into segments but impose no constraint of their own — any number of bulbs may sit next to them.
- Why is my board wrong when everything is lit?
- Almost always two bulbs shining on each other along a clear row or column, or a numbered wall touching the wrong count of bulbs. Both must be fixed for the win, not just full lighting.