How Long The Warts Take To Die After Applying Salicylic Acid On Foot?

I have two plantar warts on the bottom of my foot that I have been treating with an over the counter wart remover (Salicylic acid) for several weeks. The skin has been peeling off and I have been soaking the foot and filing off dead skin before reapplying the treatment. The warts themselves have turned white with little black dots. How can I tell when the warts are dead and can stop applying the treatment?