Superfat is the calculated amount of unsaponified oil left in a soap bar. The average superfat is five to eight percent. The higher the superfat percentage, the softer the bar tends to be. But exceptions exist in certain cases. In pure coconut body soap bars, the superfat can be as high as 15% to 20% due to its extremely cleansing effect that could strip skin if the extra oil was not left unsaponified. In a laundry coconut soap, the superfat can be as low as zero percent. The superfat used in a recipe depends on the usage of the soap bar being created. The superfat also serves as a bit of a buffer to avoid a lye-heavy soap, which could cause irritation or burns on the skin.