Sillago is a genus of fish in the family Sillaginidae and the only non-monotypic genus in the family. Distinguishing the species can be difficult, with many similar in appearance and colour, forcing the use of swim bladder morphology as a definitive feature. All species are benthic in nature and generally coastal fish, living in shallow, protected waters although there are exceptions. Minor fisheries exist around various species of Sillago, making them of minor importance in most of their range. This genus has the widest distribution of any smelt-whiting genus, spanning much of the Indo-Pacific. The genus ranges from the east coast of Africa to Japan in the east and Southern Australia in the south, with most species concentrated around South East Asia, the Indonesian Archipelago and Australia. Many species have overlapping distribution, often making positive identification hard.

The Sillaginidae, commonly known as the smelt-whitings, whitings, sillaginids, sand borers and sand-smelts, are a family of benthic coastal marine fish historically classified in the order Perciformes, although the 5th edition of Fishes of the World places the family in the Spariformes. The smelt-whitings inhabit a wide region covering much of the Indo-Pacific, from the west coast of Africa east to Japan and south to Australia. The family comprises only five genera and 35 species, of which a number are dubious, with the last major revision of the family in 1992 unable to confirm the validity of a number of species. They are elongated, slightly compressed fish, often light brown to silver in colour, with a variety of markings and patterns on their upper bodies. The Sillaginidae are not related to a number of fishes commonly called 'whiting' in the Northern Hemisphere, including the fish originally called whiting, Merlangius merlangus.