Sea Battle is a two-player hidden-information game played on 10×10 grids. Each side secretly deploys five ships — Carrier (5), Battleship (4), Cruiser (3), Submarine (3), Destroyer (2) — in straight horizontal or vertical lines with no overlap. Players alternate firing one shot per turn at the enemy grid; each shot is reported as a hit or a miss, and when all squares of a ship are hit it is sunk. The first player to sink all five enemy ships wins.
Play now — it's freeEach player has a 10×10 ocean grid of 100 squares, referenced by column letter A–J and row number 1–10.
The fleet is identical for both sides and totals 17 squares:
| Ship | Count | Length |
|---|---|---|
| Carrier | 1 | 5 |
| Battleship | 1 | 4 |
| Cruiser | 1 | 3 |
| Submarine | 1 | 3 |
| Destroyer | 1 | 2 |
Ships may not overlap or hang off the grid, and every ship is a single straight line — horizontal or vertical, never diagonal.
Both players place their whole fleet in secret before the first shot.
On this site deployment is limited to 60 seconds; if the timer runs out, a valid random fleet is placed automatically so the game never stalls.
Ships are allowed to touch each other here (the stricter "no touching" tournament rule is a common house variant we do not enforce).
The player who joined the table first fires the opening shot; from then on the players strictly alternate, one shot per turn.
A hit does not grant an extra shot — after every shot, win or lose, the turn passes to the opponent. (The "salvo" variant where you fire as many shots as you have surviving ships is a known house rule, not played here.)
You may not fire at a square you have already hit or missed.
Each shot has a 40-second allowance; an automated assistant fires when the time runs out.
Every shot is answered with hit or miss. Mark both grids as you go — bookkeeping is half the game.
When the last remaining square of a ship is hit, the shot is answered "sunk" with the ship's name: "You sank my Cruiser!"
A sunk ship's squares are all known hits, which is valuable aiming information for the surrounding water.
The first player to sink all five enemy ships wins the game. There are no draws in normal play.
Hunt with parity: firing on a checkerboard pattern guarantees every shot can reach at least one square of the smallest ship (the 2-square Destroyer).
Switch to target mode on a hit: probe the four neighbours, then extend along the line once you have two hits in a row.
Edge awareness: ships hug edges and corners surprisingly often — clear the border systematically.
After a sunk call-out, mentally retire that line: the squares around a sunk ship rarely hide another ship of the same line.
Track everything: the player who never forgets a called square never wastes a shot.
Sea Battle is the classic two-player hidden-information naval game (publicly known since the pencil-and-paper era): each side secretly deploys five ships on a 10×10 grid and the players alternate calling shots until one fleet is sunk.
The standard fleet is one Carrier (5 squares), one Battleship (4), one Cruiser (3), one Submarine (3) and one Destroyer (2) — 17 squares per side.
Each ship occupies a straight horizontal or vertical run of its length. Ships may not overlap or extend past the grid; on this site ships may touch each other.
No. Here every turn is exactly one shot and the turn then passes — the most common rule in online play. The multi-shot "salvo" variant is a separate house game.
The player who joined the table first takes the opening shot, then play alternates.
Sink all five enemy ships. A ship sinks when every square it occupies has been hit; the sinking shot is announced with the ship's name.
Yes — play free in your browser at seabattle.yeeqia.com, no download and no sign-up required.
Yes, the site is mobile-first and runs in any modern browser on Android or iPhone, with full English support.