| Planachaux | |
| Elevation M: | 1925 |
| Prominence M: | 287 |
| Prominence Ref: | [1] |
| Parent Peak: | Dent de Corjon |
| Map: | Switzerland |
| Location: | Vaud, Switzerland |
| Range: | Swiss Prealps |
| Coordinates: | 46.4442°N 7.0547°W |
The Planachaux is a mountain of the Swiss Prealps, located south of Rossinière in the canton of Vaud. It overlooks the Lac de l'Hongrin on its south side.