The kinglets are a small group of birds.
Kinglets range in size from 9 to 11 cm and are amongst the smallest of the passerines, and indeed of all birds. They have medium-sized wings and tails. The bill is small and needle-like. The plumage is overall gray-green. Most have an eye-ring or a stripe at the supercilium, although the slightly atypical Ruby-crowned Kinglet lacks this. The males possess a colourful crown patch.
Generally kinglets are adapted to conifer forests, although there is a certain amount of adaptability and most species will use other habitats, particularly during migration.
They habitually flick their wings as they hop and flit among twigs and leaves.
The tiny size and rapid metabolism of kinglets means that they must constantly forage in order to provide their energy needs. They will continue feeding even when nest building. Kinglets prevented from feeding may lose a third of their body weight in twenty minutes and may starve to death in an hour. Kinglets are insectivores, preferentially feeding on insects such as aphids and springtails that have soft cuticles. Prey is generally gleaned from the branches and leaves of trees, although in some circumstances prey may be taken on the wing or from the leaf litter on the ground.