Rules
Battleships is a fleet puzzle. Every cell is ship or water. Each ship is a straight line of 1, 2, 3, or 4 cells, across or down. Ships never touch, even at a corner. The number left of a row, and above a column, is how many ship cells that line holds. A 0 is printed. The bars under the grid are the fleet, those lengths and no others.
A triangle points toward the rest of its ship. A bar in the grid is a middle. A round mark is a one-cell ship. Those marks are locked, and so is an extra ship printed in a cell. You mark the rest. Water is part of the answer. It is not a pencil note. The puzzle is finished when every cell is marked, the ships match the fleet, and every count is right. Play is 6×6, 8×8, and 10×10, and each of those is easy, medium, and hard. The daily puzzle is an 8×8 easy grid.
Tents also uses a count beside each row and above each column, and its objects do not touch. There you place one tent beside each tree. Here you place a straight fleet, and the count is ship cells.
- Every cell is ship or water. Each ship is a straight line of 1, 2, 3, or 4 cells, across or down. Ships never touch, even at a corner.
- The count is ship cells. The number left of a row, and above a column, is how many ship cells that line holds. A 0 is printed.
- The fleet is the bars under the grid. Those lengths, and no others. A triangle, a middle bar, a round one-cell mark, and an extra printed ship are locked.
- Water is part of the answer. The puzzle is finished when every cell is marked, the ships match the fleet, and every count is right.
Ships sit at row 2 columns 2–3, row 3 columns 5–6, row 4 column 3, row 6 columns 2–4, and row 6 column 6. Everything else is water. The fleet under this 6×6 is 3, 2, 2, 1, 1, so there is no ship of length 4. On screen the three printed segments stay the end and the middle, now teal, and the ships you placed are rounded squares, teal. The counts are teal, including the three zeros. A grid of ships alone is not finished. Water is part of the answer on screen. A printed answer draws one bar for each of those runs and a cross in every water cell. It does not draw the live hulls.
- End
- Middle
- One-cell ship
- Water
- Ship you place
- Count that matches
The round one-cell mark can sit in the key. These teaching grids do not print one. The fleet still includes one-cell ships, and they show up as the small bars and, later, as a ship you place.
Click or tap an open cell to cycle empty, ship, and water. Shift-click, right-click, or a long-press of about half a second cycles the other way. Drag across open cells to paint water. A locked segment or an extra printed ship does not take a new mark. Selecting it only moves the cursor. Arrow keys move and stop at the edge. The first arrow, when nothing is selected, selects the top-left cell and does not move further. S or 1 places a ship. W, X, M, period, or 2 marks water. Backspace, Delete, or 0 clears the cell. Space or Enter cycles forward. Shift with Space or Enter cycles backward. There is no separate ship tool. M marks water.
Press Hint for one step the rules already force, with a sentence saying why. Hint lights the cells it writes, and the count when the step is about a line. Press Check when you want the board checked. A legal unfinished board gets "No mistakes so far. Keep going!" A broken board gets "Something breaks the rules. Look for the marked cells and counts." Hint on a broken board gets "This board has a mistake, so there is no hint yet." If Hint finds nothing on a legal board, it says "No forced cell from here. A ship or some water may be in the wrong place, so try Check or Undo." Undo and Redo step through the moves. Reset clears every ship and every water mark you placed. The counts, the segments, and the fleet stay. When the grid is right, the board turns teal. The dialog title is "Solved!" The dialog body is "Every ship is straight, ships do not touch, and every count matches." The Mistakes counter counts how many times Check found a broken board. It is not a score.
One press writes one step and stops. A middle writes the cells still open around that bar. The bar itself stays as it is. A 0 writes every cell on that line that is still open. A cell a segment already watered is not written again. Easy grids follow from the segment marks, the zero lines, and the counts. A 6×6 easy grid finishes without a ship that has to grow. The daily 8×8 is where that ship shows up. Harder grids look at a whole line, then at one careful try.
A count turns teal when the ships on that line already match it, even if some cells are still empty. A printed 0 is teal before you mark any water. A count turns coral when the line has too many ships, or when the open cells cannot reach the count. Ships that touch at a corner, and a ship that bends, turn those cells coral while error highlighting is on. A line that is only over or short washes the whole line a lighter coral and turns the count coral. With error highlighting off, none of that coral is drawn, and an over count is not coral either.
- Undo
- Redo
- Reset
- Hint
- Check
First marks
Start with the marks already printed. A middle grows both ways. An end grows one cell the way it points, and the cell behind it is water. A ship and another ship do not touch, even at a corner, so the open corner is water. Every grid in this article opens on one of those segments. A later 0 is still its own section.
A middle segment Easy
A bar in the grid is the middle of a ship. It grows one cell each way along the bar, and the cells straight off its sides are water. The middle grows both ways. The button writes every still-open cell of that force, in one press. On this figure the middle is row 6 column 3, horizontal. The cell itself is already a ship, so the press leaves it alone. It writes ship at row 6 column 2 and row 6 column 4, and water at row 5 column 3. The sentence is about the segment. The press is those three cells. No count lights. The grid is not finished.
The same idea is the first press on every grid here. A later 0 is still the next group of sections. Row 1, row 5, and column 1 are already teal, because their count is 0. Column 5 is teal as well: the end at row 3 column 5 is already that column's one ship.
Amber sits on row 6 column 4, row 6 column 2, and row 5 column 3. The new ships are violet on the amber tile. The new water is the teal waves on the amber tile. The middle at row 6 column 3 stays a sunken bar, unlit. No count turns amber. The two ends stay as they were. The grid is still unfinished, so the toast shows. Hint says "This ship segment forces the cells around it."
An end segment Medium
A triangle is an end. It points toward the rest of the ship. The next cell that way is ship. The cell behind the triangle is water, and so are the two cells beside it. The button writes the open cells of that force. It leaves the triangle as it is. On this figure the end is row 4 column 3 and it points south. The press writes ship at row 5 column 3, water at row 3 column 3, water at row 4 column 4, and water at row 4 column 2. No count lights. The grid is not finished.
This puzzle also prints one extra ship, the square at row 3 column 1. It is locked. Row 3's count is 1, so that count is already teal. Column 4 is a 0, so that count is teal too, and this press does not light it. The extra square is part of some medium and hard grids. The easy grids in this article do not have one. This press is still the segment, so an easy puzzle offers it too. The later "only place" on this same board is a different step, one ship at row 6 column 3, and it is not drawn.
An end on the edge has fewer neighbours, so the press is shorter. On another 6×6 easy grid the end writes two cells, ship at row 4 column 1 and water at row 2 column 1. That grid is not drawn.
Amber sits on the ship at row 5 column 3 and the water at row 3 column 3, row 4 column 4, and row 4 column 2. The end and the extra ship stay unlit. Column 4's 0 stays teal. Hint says "This ship segment forces the cells around it."
Water on the diagonal Easy
Ships do not touch, even at a corner. Once a ship is on the board, each open cell on its diagonal is water. The button writes those open corners and stops. It leaves the ship as it is. On this figure the ship at row 2 column 3, the cell the end just grew into, has one open corner left, row 3 column 3. The press writes water there. No count lights. The grid is not finished.
The same press can write several corners. The next press on this board writes four: row 2 column 4, row 2 column 6, row 4 column 4, and row 4 column 6, around the end at row 3 column 5. The drawn figure is the one cell, so the toast is easy to point at. The cells straight off the side of a longer ship are water too. On these grids that water was already written by the segment or by a corner, so the button does not use a separate sentence for it. The sentence it knows is "The sides of this ship are water."
A count of 0 would come before this corner in the order the button tries. On this grid the three zeros are the presses just before this one. The article teaches the corner here, with the other marks that come from a ship, and the 0 in the next section.
Amber sits on row 3 column 3 only. The new mark is water on that tile. The ship at row 2 column 3 stays an ordinary violet square. No count lights. Hint says "A ship stands on the diagonal, so this cell is water."
The counts
The number is how many ship cells that line holds. A 0 is all water. A line that already has its ships takes water in the open cells. A line that still needs a ship in every open cell takes a ship in each of them. One press writes that line's open cells, and it lights the count.
A count of 0 Easy
A 0 means the whole line is water. The button writes every cell on that line that is still open. A cell a segment already watered is not written again. On this figure row 3 is a 0, and all six cells are still open. The press writes water on row 3 column 1 through row 3 column 6. The count lights while the hint is showing, even though a 0 was already teal. After the press it is teal again. The grid is not finished.
This is not the first press. Three segments run first, and so does a 0 on the row above. On the grid in the middle section, the first 0 is row 1, and it writes five cells, because the end already put water on row 1 column 2. That press is not drawn. A 15-cell line is not drawn either.
Amber sits on all six cells of row 3, and on the row 3 count. Each new mark is water. The count was teal before the press, and the amber covers it while the hint is showing. Hint says "This line's count is 0, so every open cell is water."
Already enough Easy
When the ships already on a line equal the count, every open cell on that line is water. The count is teal as soon as the ships match, before the water is written. The button writes the open cells and lights the count. On this figure column 2's count is 2. The end at row 2 column 2 and the ship at row 6 column 2 are those two ships. The one open cell is row 4 column 2. The press writes water there. The grid is not finished.
A wider line is the same sentence. On a 6×6 medium grid, a row that already has its two extra ships writes four waters. The drawn figure is the one cell.
Amber sits on row 4 column 2 and on the column 2 count. The new mark is water. The two ships in that column stay unlit. Hint says "This line already has its ships, so the open cells are water."
Every open cell Easy
When a line still needs a ship in every cell that is left open, those cells are ship. The button writes them and lights the count. On this figure row 4's count is 1, and the only open cell is row 4 column 3. The press writes a ship there. The count was not teal before the press. It is teal after. The grid is not finished. One unknown remains, row 6 column 6.
The next press on this board fills row 6 column 6 and finishes the grid, so the live button skips that toast. The solved dialog is the sentence you see. That press is not this figure. On another 6×6 easy grid the last press writes two ships and solves. That grid is not drawn.
Amber sits on row 4 column 3 and on the row 4 count. The new ship is violet on the amber tile. Row 6 column 6 stays empty. Hint says "This line needs a ship in every open cell."
The ship itself
A ship that is too short has to grow. Medium grids then find the only slot left for the next long ship, and that press writes the ship and the water around it. Once, on a hard grid, every slot that is left covers the same cells, and the press writes those ships only. A cell no remaining ship can use is water. On these grids the earlier sentences had already written that cell, so the button does not say it on its own. The sentence it knows is "No ship can sit here, so this cell is water."
The ship has to grow Easy
A ship that is still shorter than the ships you have left has to grow into the open cell at its end. The button writes that one cell. It does not light a count. A 6×6 easy grid in this set finishes without it. The daily 8×8 is where it shows up. On this figure the open cell is row 3 column 8. The press writes a ship there. Three cells are still unknown. The grid is not finished.
A ship that is already as long as it can be takes water in the next cell. That press is not on the grids drawn here. The sentence is "This ship is as long as it can be, so the next cell is water." When only one-cell ships remain, the cells around a ship are water. That press is on a print-only 15×15, not on a size you play. The sentence is "Only one-cell ships remain, so the cells around this ship are water." The round one-cell mark in the rules is the same idea as a one-cell ship in the fleet. These grids do not print that round mark.
Amber sits on row 3 column 8 only. The new mark is a violet ship. No count lights. Three cells stay unknown. Hint says "This ship has to grow into the open cell."
The only place left Medium
Sometimes one ship length is left in only one slot. The button writes that ship, and it writes the water in the cells around it that are still open. No count lights. Easy grids do not offer this sentence. Medium grids do, after the earlier sentences have run. On this figure the press writes ship at row 4 column 3, water at row 4 column 4, and water at row 5 column 4. The end at row 4 column 1 and the ship already at row 4 column 2 are part of that run. They stay unlit. The grid is not finished.
An easy puzzle on this same picture has nothing to say. Medium is where the button starts offering the sentence. This grid still opened on a segment. Row 3 is a 0, already handled before this press.
Amber sits on row 4 column 3, row 4 column 4, and row 5 column 4. The new ship is violet. The two new waters are teal waves. The end and the ship at row 4 column 2 stay unlit. No count lights. Hint says "This is the only place left for this ship."
Every place covers this cell Hard
When more than one slot is left for a ship, and every one of those slots covers the same cells, those cells are ship. The button writes the ships. It does not write the water around them. No count lights. This is not the medium sentence. The medium grids in this set say "the only place", and they stop there. The one time the button says this overlap, it is a hard 8×8. On this figure the press writes ship at row 2 column 4 and row 3 column 4. The grid is not finished.
An easy puzzle does not offer this sentence. A cell that no remaining ship can sit in is water, and the button knows "No ship can sit here, so this cell is water." On these grids an earlier sentence had already written that cell.
Amber sits on row 2 column 4 and row 3 column 4. Both new marks are violet ships. No water is written. No count lights. Hint says "Every place left for this ship covers this cell."
What if
A hard grid can still have a line, a ship, or one cell that you try both ways. The line's press writes a neighbour, not a cell on the line itself. The ship's press writes every cell the surviving places agree on. The one-cell press writes the mark that can be finished, and leaves the other mark off the board.
Off this line Hard
A hard grid can look at every way to finish one line. When every way covers a cell next to that line, the cell is water. The button writes the neighbour and lights the line it was reading, not the neighbour's own count. On this figure it is reading row 7. The cell it writes is row 8 column 4, on the next row. The grid is not finished.
The same look can force a cell on the line itself. The button knows "Every way to finish this line puts the same mark here." It did not use that sentence on these grids. The press that did run is the neighbour. A 6×6 hard grid in this set does not say this. The first size that does is 8×8 hard. The largest press of this kind writes two waters. This figure writes one. A 10×10 is not drawn. An easy puzzle and a medium puzzle have nothing to say on this picture.
Amber sits on row 8 column 4 and on the row 7 count. The new mark is water. Row 8's count stays ordinary. Hint says "Every way to finish this line covers the neighbouring cell, so that cell is water."
Every place for the next ship Hard
Place the next ship in every slot that is still legal, and keep going. Some of those slots break the fleet. The slots that do not break it can still agree on a few cells. The button writes the cells they agree on, ship or water, and stops. On this figure it writes water at row 1 column 4, water at row 4 column 2, and ship at row 4 column 4. Nine cells stay unknown. The grid is not finished, so the toast shows.
On a 6×6 hard grid this sentence is the last press, and it solves the board. The solved dialog replaces the toast. That finish is not drawn. A press that fills most of a 10×10 is not drawn either. Easy and medium have nothing to say on this picture.
Amber sits on row 1 column 4, row 4 column 2, and row 4 column 4. Two of the marks are water. One is a violet ship. No count lights. Nine cells stay unknown. Hint says "Every legal place for the next ship settles this cell."
The other mark fails Hard
One open cell can be tried both ways. If a ship there cannot be finished, the cell is water. If water there cannot be finished, the cell is ship. The button writes that one cell and lights nothing else. It does not write a second cell that both tries happened to share. On this figure water at row 1 column 1 cannot be finished, so the press writes a ship. Seven cells stay unknown. The grid is not finished.
The same sentence can write water. The one time it does in this set is a 10×10 hard grid, at row 5 column 2. That grid is not drawn. The toast is the whole explanation: "The other mark here contradicts the fleet, so this cell is settled." Easy and medium have nothing to say on this picture.
Amber sits on row 1 column 1 only. The new mark is a violet ship. No count lights. Seven cells stay unknown. Hint says "The other mark here contradicts the fleet, so this cell is settled."
Common mistakes
Check paints a broken rule. Hint will not explain a board that is already broken. The toast is "This board has a mistake, so there is no hint yet." A wrong ship or a wrong water can also sit there with no coral at all. Then Check says "No mistakes so far. Keep going!" and Hint still offers the next real step. The wrong mark stays until a later step writes that cell, or until you clear it.
The end at row 2 column 2 is already a ship. A ship at row 3 column 3 touches it at a corner. Both cells are full coral. No count is coral. Row 3 already has its two ships, so that count is teal. Column 3 still has room. Nothing is amber. Hint on this board says "This board has a mistake, so there is no hint yet."
Row 4's count is 1. Six waters cannot reach it. The count is coral. The six cells take the lighter line wash. There is no corner touch and no bend. Nothing is amber. The same toast applies: "This board has a mistake, so there is no hint yet." A line that already has too many ships paints the count and the line the same way. A ship with two side neighbours is coral on its own. That bend showed up only inside a stack of other breaks, so it is not drawn here.
The corner and the short line are the pictures of Check. A wrong mark Check does not see yet is the other picture. With error highlighting off, the corner and the short line paint nothing coral.
The ship at row 3 column 4 sits beside the end at row 3 column 5, in a straight line, so it is not a corner touch and it is not a bend. Row 3's count is 2. The end is one ship and this cell is the second, so the count turns teal. Column 4's count is 1, so that count turns teal too. The ship is still the wrong cell. The real second ship in that row is row 3 column 6. Check says "No mistakes so far. Keep going!" The amber is the opening middle, the same three cells as the first figure, and this ship is not among them. The wrong ship stays.
Water at row 6 column 6 is a ship in the solution. Row 6's count is 4 and the middle is already one ship, so one water does not make the line short. Nothing touches. No coral. The opening middle is unchanged, and this cell is not in that write, so the wrong water stays. Check says "No mistakes so far. Keep going!"
What to play next
Easy grids follow from the segment marks, the zero lines, and the counts. Start there. A 6×6 easy grid is the short start. It finishes without a ship that has to grow. The daily puzzle is 8×8 easy, and that size is where a ship has to grow. Medium grids add the only place left for a ship. The earlier sentences still come first, and a medium grid still opens on a segment. Some medium grids have no 0. Hard grids add a line that forces a neighbour, a ship you try in every remaining place, and one cell whose other mark fails. A 6×6 hard grid uses the ship or the one cell. The neighbour shows up from 8×8 hard. The overlap, where every place covers the same cells, is one hard step, not the usual medium step.
- Easy6×6The segment marks, the 0s, the corners, a line that is already full, and a line you fill. No ship that has to grow.Play 6×6 →
- Easy8×8The same sentences, plus a ship that has to grow. This is the daily size.Play 8×8 →Today's daily →
- Hard6×6The next ship, or the one cell whose other mark fails. Not the neighbour off the line.Play 6×6 →
- Hard8×8The neighbour, the next ship, and the one cell. One of them also says that every place covers the same cells.Play 8×8 →
12×12 and 15×15 are for print only, and only at easy. A printed answer draws each ship as one bar and a cross in every water cell. Four 6×6 grids share a sheet. Two 8×8 or 10×10 grids share a sheet. A 12×12 or a 15×15 has the sheet to itself. The printable page is Battleships packs.