Kilb is a town in the district of Melk, in the Austrian state of Lower Austria. It lies in the western part of Lower Austria, in the region known as the Mostviertel, roughly midway between the towns of Melk to the north and St. Pölten to the east.
The surrounding countryside is hilly and largely agricultural, typical of the Alpine foothills that characterize this part of Lower Austria. The town is a small, quiet settlement rather than a major urban centre, and it functions chiefly as a local residential and farming community within the Melk district.
Kilb is one of several municipalities that make up the district of Melk, an administrative area centred on the town of Melk and its well-known Benedictine abbey. The town is served by local roads connecting it to neighbouring communities in the district.