The Kirkland Signature (Costco) Ultra Clean Free & Clear is part of the Laundry detergent test program at Consumer Reports. In our lab tests, Laundry detergent models like the Ultra Clean Free & Clear are rated on multiple criteria, such as those listed below.

Body oil: Indicates how well a detergent removes body oil or "Sebum".

Dirt: Indicates how well a detergent removes dirt or "Clay".

Grass: Indicates how well a detergent removes grass stains.