Thai Morse encodes the 44 consonants of the Thai alphabet (and selected vowels and tone marks) as Morse patterns. It was developed for Thai telegraphy in the late 19th century and remains in use among HS-prefix amateur radio operators.
Thai Morse was created during King Chulalongkorn's modernization of Siamese telegraphy in the 1880s. It adapted the international Morse framework to Thai consonants while leaving vowels and tone marks largely implicit (recovered from context).
Thai amateur radio operators use it for Thai-language QSOs. The Royal Thai Armed Forces historically used it for domestic communications.
Most Thai vowels are written above, below, before, or after consonants, and they're typically inferred from context in Morse rather than transmitted explicitly. A few standalone vowel codes exist for cases where context isn't enough.
Tone marks have assigned Morse codes but are often omitted in casual transmission, with the receiver inferring tones from context. Formal messages include them.
HS-prefix Thai amateur radio for native-language QSOs. Operational maritime, aviation, and military communications now use International Morse or digital modes.
Explore all Morse code variants → Morse Code Variants Around the World
