An order for 36 D.XXIs was placed in the summer of 1937.
- Fokker: 39, 46
- Danish Royal Army Aircraft Factory: 10
- VL (Finnish State Factory): 90
- Total: 146
In 1937 Finland ordered seven production models and an agreement was made to allow the Finns to license built the D.XXI.
The State Aircraft Factory constructed 93 fighters during 1938 to 1944.
The first 38 had Bristol engines. The next 50 had American Pratt & Whitney Twin Wasp Junior radial engines (836 HP / 1,050 HP). The last five had Bristol Pegasus engines.
Denmark constructed ten aircraft under license.