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How to solve Pinplot

Every Pinplot board has exactly one answer, and you can always reach it by logic. This guide covers the techniques that do the work, and walks through a real puzzle from start to finish.

The rules in one minute

The grid is split into colored regions. Place stars so that:

• every row has exactly one star,
• every column has exactly one star,
• every region has exactly one star,
• and no two stars touch, not even diagonally.

A 5×5 board has five stars, an 8×8 board has eight. If you know Star Battle puzzles, Pinplot is the one-star version.

Stars and crosses

Tap a cell once to mark it with ✕ ("no star here"), again for a star, and a third time to clear it. Crosses are the real tool: most of the solving is crossing out cells until only one option is left somewhere.

Four techniques that solve almost every board

1. Last cell standing

If a row, column or region has only one cell left that isn't crossed out, the star goes there. This includes the easiest case of all: a region made of a single cell.

2. A region trapped in one line

If all the remaining cells of a region sit in one row, then that row's star must be inside the region. So every other cell in that row can be crossed out. The same works for columns, and it also works the other way round: if all the remaining cells of a row sit inside one region, the rest of that region is crossed out.

3. Don't block a neighbor

Before placing a star, ask what it would cross out. If a cell touches every remaining cell of some row, column or region, a star there would leave that row, column or region with no possible star. So that cell can be crossed out.

4. Count regions

On bigger boards, look for two regions that both fit entirely inside the same two rows. Those two rows need two stars, and these two regions need two stars, so the two regions use up both rows: every other cell in those two rows can be crossed out. The same works with three regions in three rows, and with columns.

A full example, step by step

Here is a real 5×5 board from the game, the size you get on Mondays. Rows are numbered from the top and columns from the left.

Step 1: last cell standing. The region at row 4, column 5 is a single cell, so it must hold a star. Cross out its row, its column and its neighbors.

Step 2: a region trapped in one line. After step 1, the bottom region has only two cells left, and both are in column 3. So column 3's star belongs to that region, and the other cells of column 3 (row 1, row 2) are crossed out.

Step 3: don't block a neighbor. Look at row 2, column 1. It touches every remaining cell of the top-left region, so a star there would leave that region empty. Cross it out.

Step 4: the same idea again. Row 2, column 2 touches all the open cells of row 3. Cross it out too.

Step 5 onward: last cell standing, four times. Row 2 now has only one open cell, at row 2, column 4: star. That leaves column 3 with one cell, at row 5, column 3: star. The left region is down to row 3, column 1: star. And row 1 has one cell left, at row 1, column 2: the last star. Solved, without a single guess.

Getting faster

Scan the small regions first

Your time is the score, and most boards have one or two tiny regions that give away the first star. Find them before anything else.

Cross out as you go

It's tempting to keep the crosses in your head. Don't: each cross you place makes the next "last cell standing" easier to spot, and that is where most stars come from.

Never guess

If you are stuck, a guess feels faster, but undoing a wrong guess costs far more time. Go back through the four techniques in order; one of them always applies.

Boards grow from 5×5 on Monday to 8×8 on the weekend, each with its own par time for three stars. Practice mode has unlimited boards at every size, with hints.