Semaphore Flag Translator
Type a word or phrase and see the left- and right-arm flag position for every letter, digit, and space, per the standard semaphore alphabet.
Semaphore positions
| Character | Positions |
|---|---|
| S | Left arm lowered diagonal, right arm held out to the side |
| O | Left arm crossed high, right arm held out to the side |
| S | Left arm lowered diagonal, right arm held out to the side |
Reading the positions
Picture the signaller as the center of a clock face. Each arm can point up, out to its own side, down, or to one of the diagonals in between — five “natural” positions per arm. Two further positions let an arm swing across the body to the opposite side’s high or low diagonal, which is what lets 26 letters be built from just seven positions per arm.
A message is read one letter at a time, with a brief pause — the “space” position, arms lowered — marking the gap between words.
Frequently Asked Questions
What is flag semaphore?
Flag semaphore is a signalling system in which a sender holds one small flag in each hand and spells out a message by moving their arms through a fixed set of positions — one combination of two arm positions per letter. It was standard practice for ship-to-ship and ship-to-shore signalling before radio, and it's still taught today in maritime training and scouting.
How many positions does each arm use?
Seven, named for where the flag points: straight up, a raised diagonal ("high"), held straight out to the side, a lowered diagonal ("low"), straight down, and two "across" positions where the arm crosses in front of the body at the opposite high or low diagonal. Every letter is a specific pairing of a left-arm and a right-arm position.
How are numbers signalled?
There's no separate numeral alphabet. Instead, a "numeral sign" is signalled first to tell the reader that digits follow, and then the digits 1 through 9 and 0 reuse the positions for the letters A through I and K, in order.
What happens to punctuation or accented letters?
Standard semaphore only defines the 26 Latin letters, so this translator marks anything else — punctuation, accented characters, emoji — as unsupported rather than guessing at a position, so you can see exactly what would need to be reworded for a real signaller.
Educational tool only. This reflects the standard semaphore alphabet used for teaching and historical reference — for operational maritime signalling, always train from an official manual.