A burner for a gas cooktop comprising a main body provided with a first plurality of holes capable of producing first flames at a first angle with respect to a horizontal reference plane, and a second plurality of holes capable of producing second flames at a second angle with respect to said horizontal plane, which is smaller than the first, said first and second pluralities of holes consisting of corresponding groups of holes, each group being associated with the same flame and each group consisting of at least one hole, characterized in that the total cross-sectional area of each group of holes of the second plurality of holes is greater than the total cross-sectional area of each group of holes of the first plurality of holes, such that the second flames are more powerful than the first flames.