What does the "72%" marking on this soap mean and how does it affect cleaning performance?

The "72%" marking indicates the proportion of fatty acids in the soap base. This is a traditional industry standard for household soap in many countries. In practical terms, a higher fatty acid content means more soap molecules are available to surround and lift away grease, oil, and particulate dirt so they can be rinsed off with water. The 72% grade has been the benchmark for general-purpose laundry and cleaning soap for decades because it balances cleaning power with a firm bar that doesn't dissolve too quickly. Lower percentages (such as 65% or 60%) contain more fillers and water, so they wear down faster and require more product for the same cleaning task. This 180 g bar at 72% will last through many hand-wash sessions or spot treatments because the concentration is high — you only need a thin layer of lather on the fabric or surface.