IL-13 is a biomarker of type 2 inflammation that plays a critical role in asthma. IL-13 is present in serum at subpicogram levels. Simoa HD-1 technology was evaluated for the detection and quantitation of IL-13 by using a commercially available IL-13 kit and compared with a Simoa HomeBrew (HB) IL-13 assay as well as Immunological Multi-Parameter Chip Technology (IMPACT), an internal Roche platform. Performance of the assays was evaluated based on preset criteria for sensitivity, standard curve and controls' accuracy and precision, reproducibility and parallelism of endogenous analyte in serum samples. The Simoa platform offered high assay sensitivity for evaluation of IL-13. This paper discusses the challenges and considerations when evaluating kits and/or developing HomeBrew assays using ultrasensitive platforms.