Klasov is a village and municipality in the Nitra District in western central Slovakia, in the Nitra Region.
In historical records the village was first mentioned in 1232.
The village lies at an altitude of 177 metres and covers an area of 12.231 km². It has a population of about 1,210 people.
The village is approximately 55% Slovak, 45% Magyar
The village has a public library and football pitch, tenis pitch in penzion Agroland.
The records for genealogical research are available at the state archive "Statny Archiv in Nitra, Slovakia"
Coordinates: 48°17′N 18°16′E / 48.283°N 18.267°E / 48.283; 18.267