GTT or gtt may refer to:
Science and technology
- Global title translation, in telecommunications
- Glucose tolerance test, a medical test
- Google Translator Toolkit, a web application
- Graphics translation table, an I/O memory management unit
- Drop (unit) (gtt), an approximated unit of measure of volume
Other uses
- Georgetown Airport (Queensland) (IATA code), Australia
- Gone to Texas, Americans emigrating to Texas in the 19th century
- Gruppo Torinese Trasporti, a public transport company in Turin, Italy
- GTT Communications, Inc., an American telecommunications company