Maritime signal flags form the International Code of Signals (ICS), a system that lets vessels of any nationality exchange safety and navigation messages without a shared spoken language. Each letter of the alphabet has a uniquely coloured flag with its own name and a defined meaning when flown alone. This encoder spells any text using those flag names and shows each flag’s standalone significance.
How it works
The ICS assigns 26 alphabet flags, named Alfa, Bravo, Charlie, …, Zulu (note Alfa and Juliett are spelled to match the NATO alphabet). When encoding, the tool maps each letter to its flag name and appends a short note of the flag’s single-flag meaning, such as A — Alfa (Diver down; keep clear).
Spaces separate words, and any digit is labelled as a numeral pennant because ICS sends numbers with dedicated pennants rather than letter flags. The output is a plain-text list, one labelled line per character.
Example
Spelling SOS produces three lines: S — Sierra (My engines are going astern), O — Oscar (Man overboard), S — Sierra (...). Hoisting Oscar alone is itself the recognised man-overboard signal, which is why these single-flag meanings matter at sea.