We come across a lot of people seeking "the best swim soap" or a "soap for washing chlorine off after swimming" or a "soap for swimmers" or a "swimmers' soap."
Here's the answer: there is no "best" anti-chlorine soap. Soap does not wash chlorine off of hair and skin. Soap is formulated to remove dirt and grime from the surface of hair and skin. It does not have the correct ingredients for eliminating chlorine.
If you read the ingredients on your soap, you will find some combination of water, surfactants, lathering agents, and fragrances. These ingredients provide the users with lather, scent, and the ability to wash away oil and dirt. These ingredients do NOT release chlorine from the surface of hair and skin. (That's why swimmers notice that they smell like chlorine even after showering).
When swimmers go in the pool, the pool chlorine chemically reacts with the surface of their hair and skin. It bonds to hair and skin. It sticks there chemically. You may notice that it is very difficult to wash away. (That's why you smell like chlorine long after leaving the pool).
In order to get the chlorine off of hair and skin, you need an ingredient that neutralizes chlorine's bond to the hair and skin. Chlorine oxidizes hair and skin. It forms a layer of chloramines. Using a powerful antioxidant will eliminate this layer. An antioxidant will release chlorine's bond to the hair and skin. Then, the chlorine easily washes away.
Why do I know about this? Well, I'm a little bit obesessed with chlorine. I am a PhD chemist and lifelong swimmer. Check out the video below to get the whole story in under 3 minutes.
Don't believe me? Try it. You will notice the very first time that the chlorine odor disappears, indicating that the lingering chlorine is washed away from your body. Your hair and skin will feel healthier for it.