Cognomen 朗格 (Longe 
, Runge 
, Loog 
) , all around the world, is a common last name. The surname 朗格 is habitual in Estonia, where it is quite a common surname, Germany, and Denmark, where it is quite a rare surname. Not in comparison with a country's population, it is commonest in Germany, the United States, and Nigeria. Much less frequently, 朗格 is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Longe | Canada, Nigeria, United States, Democratic Republic of the Congo, Germany |
| Runge | Canada, Nigeria, United States, Germany, Denmark |
| Loog | Canada, United States, Germany, France, Indonesia |
| 朗格 | China |