Los 40 is Spain's leading music radio station, broadcasting contemporary hits 24 hours a day. Founded in 1966 as a music program on Radio Madrid, it evolved into an independent radio station in 1979. Los 40 primarily targets listeners aged 12-30, playing the latest pop, dance, and urban music. The station is known for its youthful, dynamic style and casual language that appeals to young audiences.

Los 40's programming includes hit music, artist interviews, entertainment news, and interactive content. It has expanded internationally to several Spanish-speaking countries. The station can be accessed via FM radio, digital terrestrial television, online streaming, and mobile apps.

As part of the PRISA media group, Los 40 has become a cultural icon in Spain, hosting major music events like the Los 40 Music Awards. The station continues to shape the Spanish music scene by promoting both established and emerging artists.