KDA or similar may refer to:
- Combat Groups of the Working Class (German: Kampfgruppen der Arbeiterklasse), a paramilitary organization in East Germany
- Karachi Development Authority, an urban development organization in Karachi, Pakistan
- Kilodalton (kDa), 1000 unified atomic mass units
- Kongsberg Defence & Aerospace, a Norwegian supplier of defence and space related systems and products
- Kotelawala Defence Academy, a Sri Lankan joint services academy now called Kotelawala Defence University
- Kramer Design Associates, a Canadian graphics design company
- Potassium diisopropylamide, a strong base used in organic chemistry similar to lithium diisopropylamide
- Worimi language, an Australian Aboriginal language