FM O Dia broadcasts under the slogan "Alegria que irradia," joy that radiates, and for ten straight years the ratings backed that claim up: it was the most-listened FM station in Rio de Janeiro and Greater Rio, not just among music stations, but across the entire dial.
A Frequency Swap and a New Owner
Per Wikipedia's entry on FM O Dia, the station first went on air on May 1, 1994, at 90.3 MHz in Rio's Andaraí neighborhood, playing an adult contemporary format under different ownership. The station that exists today traces to Ary Carvalho, founder of the O Dia newspaper group, who relaunched it as part of Grupo O Dia in December 1997, the same period the station moved to its current 100.5 FM frequency and pivoted hard toward Brazilian popular music: samba, pagode, and the funk carioca sound rising out of Rio at the time. The station is now run by Gigi Carvalho.
A Decade at the Top of Rio's Ratings
That pivot paid off. According to the same source, FM O Dia was the general audience leader among all FM stations in Rio de Janeiro and Greater Rio for ten consecutive years, per ratings agency IBOPE, and by February 2022 it had again pulled ahead to become the leading station across Rio de Janeiro state. For a station built inside a newspaper's media group rather than a dedicated broadcasting company, a decade at the top of a market as competitive as Rio radio is a rare run.
From One City to a Growing Network
FM O Dia has since expanded beyond Rio itself. Wikipedia notes the station began adding affiliate stations in Amazonas and Pará states starting in 2017 and 2018, and picked up another affiliate in Vitória, Espírito Santo, in 2024, turning a single Rio frequency into the anchor of a small regional network. The playlist today spans samba, pagode, pop, axé, university sertanejo, hip hop, rap, reggae, trap, and funk carioca, a wide net built to hold the audience it spent a decade winning.
Why It's Worth Tuning In
FM O Dia offers a look at Rio radio from the station that, for ten years running, more of the city tuned into than any other FM signal, still broadcasting the same mix of Brazilian genres that took it there.