- Kingdom: Animalia
- Phylum: Chordata
- Subphylum: Vertebrata
- Superclass: Gnathostomata
- Class: Actinopterygii
- Order: Gadiformes
- Family: Gadidae
- Scientific name: Micromesistius poutassou
- Norwegian: kolmule
The blue whiting may reach a maximum body length of 50 cm. The body is slender and silver colored, with a bluish tint on the back. The three dorsal fins are widely spaced. The spacing between second and third fins are longer than the base length of the first two dorsal fins. The lateral line runs in full body length. It has no barbell.
The blue whiting makes vertical migrations daily and may come shallow enough to be encountered by divers on night dives. It can be found along the entire Norwegian coast.
There is an increasing commercial interest in the blue whiting in the north eastern parts of the Atlantic Sea. It lives on depths between 50 and 1500 metres. Spawning does happen locally along the Norwegian coast, but the major population spawns around Ireland in March and April, before migrating back to the Norwegian Sea, passing on the north side of the British Isles. A separate population is found in the Barents Sea.