Brake light will not turn off

Brake light stays on when driving and when the car is off. I changed the brake switch after checking on the web for some results. But that did not fix the problem. I also tried changing the fuse inside the car fuse box with another fuse the same size that did not work either. I hear there might be a relay switch but have no clue where to find it. I checked the fuse boxes in the engine did not see one mark for the brake light. Any suggestions on how to fix? When I press the brake switch the light gets brighter, instead of going off.