There are 4 standard time zones in Brazil:
BRT - Brasília (Standard) Time
AMT - Amazon (Standard) Time
FNT - Fernando de Noronha Archipelago Time
ACT - Acre Time
In 2019 the Brazilian governement decided that the country would no longer observe Daylight Saving Time. Source: Agencia Brasil (Brazil News Agency)
DST ended on 17 February 2019 and was due to start again on the first Sunday in November. (source: Brazilian Government site)
Historically, Daylight Saving Time (DST) or Summer Time has been observed in ten states: São Paulo, Rio de Janeiro, Espírito Santo, Minas Gerais, Paraná, Goiás, Mato Grosso do Sul, Mato Grosso, Rio Grande do Sul, Santa Catarina, and in Distrito Federal (the Federal District).
The time in most of Brazil visited by foreign tourists is Brasília Time (BRT), which is 3 hours behind Greenwich Mean Time ( GMT-3 ). BRT is in use in Rio de Janeiro and São Paulo.
Brasilia Standard Time (BRT) = GMT-3
Amazon Standard Time (AMT) = GMT-4
Fernando de Noronha Time (FNT) = GMT-2
Acre Time (ACT) = GMT-5