The western tanager (Piranga ludoviciana), is a medium-sized American songbird. Formerly placed in the tanager family (Thraupidae), it and other members of its genus are classified in the cardinal family (Cardinalidae). The species's plumage and vocalizations are similar to other members of the cardinal family.

The western tanager was illustrated and formally described by American ornithologist Alexander Wilson in 1811 under the binomial name Tanagra ludoviciana from a specimen collected on the Lewis and Clark Expedition (1804–1806). The type locality is Kamiah, Idaho. The specific epithet is from the Late Latin ludovicianus for "Louis". The name is from Louisiana, the 18th-century French administrative district of New France, rather than the modern state. The western tanager is now placed in the genus Piranga that was introduced by French ornithologist Louis Pierre Vieillot in 1808. The species is monotypic; no subspecies are recognized.

Measurements:

Adults have pale, stout pointed bills, yellow underparts, and light wing bars. Adult males have a bright red face and a yellow nape, shoulder, and rump, with black upper back, wings, and tail; in non-breeding plumage, the head has no more than a reddish cast and the body has an olive tinge. Females have a yellow head and are olive on the back, with dark wings and tail.

The song of disconnected short phrases suggests an American robin's, but is hoarser and rather monotonous. The call is described as pit-er-ick.

Their breeding habitat is coniferous or mixed woods across western North America from the Mexico-U.S. border as far north as southern Alaska; thus, they are the northernmost-breeding tanager. They build a flimsy cup nest on a horizontal tree branch, usually in a conifer. They lay four bluish-green eggs with brown spots.

These birds migrate, wintering from central Mexico to Costa Rica. Some also winter in Southern California.

The breeding range of the western tanager includes forests along the western coast of North America from southeastern Alaska south to northern Baja California, Mexico. Western tanagers extend east to western Texas and north through central New Mexico, central Colorado, extreme northwest Nebraska, and areas of western South Dakota to southern Northwest Territories, Canada. The western tanager's wintering range stretches from central Costa Rica north through Nicaragua, Honduras, El Salvador, and Guatemala to southern Baja California Sur and extreme southeastern Sonora in western Mexico and to southern Tamaulipas in northeastern Mexico. Western tanagers do not typically occur in the Caribbean lowlands. They have been reported wintering further north and have been observed as far south as Panama. Vagrants are rare to casual in the eastern United States.