Flag semaphore translator

How flag semaphore works

The signaller holds a flag in each hand and points each arm in one of eight directions: down, the two low diagonals, straight out to either side, the two high diagonals, and up. Every letter is a pair of positions. Semaphore was invented in the 1800s for ships within sight of each other and is still taught to sailors and scouts.

The figures on this page are drawn as the receiver sees them, facing the signaller. That matters, because the signaller's right arm appears on your left. A, B and C are made with the signaller's right arm, which you'll see on the left of each figure.

Learning it in circles

• A to G: one arm stays down while the other works round the clock, low, out, high, up, and over to the other side.
• H to N: one arm stays at A's position while the other goes round. (J is the exception: it was added later and uses up and straight out.)
• O to S: one arm stays at B's position.
• T, U, Y and the Annulling sign: one arm at C's position. V, W, X and Z fill the remaining pairs.

Decoding a picture

For each figure, note where both arms point, then tap the matching figure in the keyboard above. If a whole message decodes as nonsense, check that the picture is drawn from the front. A mirror-image chart swaps the sides, so A reads as G, B as F and C as E.