A basic and widely used rule of thumb is: Choose a light fixture that is approximately 75% the width of your vanity and install it directly above the mirror, about 75 to 85 inches above the mirror. In other words, assuming your vanity is 48 inches wide, the ideal bathroom vanity light should be around 36 inches wide.
Mirror lamps are lamps installed above or on both sides of the mirror, especially suitable for bathroom vanity lighting. Its main advantage is that it can provide uniform and bright light, avoiding shadows or uneven lighting.