Accurate assessment of commercial complementary food (CCF) intake among infants and young children requires both an appropriate dietary assessment method and nutrient composition data that adequately represent these foods. However, existing Australian nutrient composition databases may have limited coverage of CCFs, potentially affecting estimation of energy and nutrient intake. A novel dietary assessment tool has been developed to measure CCF intake among children aged 6–36 months, informed by a systematic literature review(1) and preliminary consumer engagement. The tool uses a category-based food frequency questionnaire-screener aligned with the World Health Organization Nutrient and Promotion Profiling Model (WHO NPPM).(2) It captures usual frequency and portion size of CCF intake, allowing standardised estimates of grams consumed. This study aimed to determine whether AUSNUT 2023 could support estimation of CCF intake using these standardised tool-derived parameters across simulated dietary scenarios. Dietary simulations were conducted for males and females aged 6, 9, 12, 18, 24 and 36 months. Age- and sex-specific estimated energy requirements (EER) were derived from Australian Dietary Guidelines, while complementary feeding patterns, including meal and snack frequency, and the proportion of energy contributed by complementary foods, were informed by WHO recommendations. Standardised CCF frequency and portion-size factors were derived from the novel dietary assessment tool. Representative serving sizes were assigned using a category-based approach informed by CCF label weights, with mean serving weights calculated where multiple products were available. Four dietary scenario targets were modelled to represent varying contributions of CCFs to complementary food energy intake: Low (25%), Medium (50%), High (75%) and Snack (50% derived from snack-style CCFs only). Energy, macronutrient and micronutrient intakes were estimated using AUSNUT 2023. AUSNUT 2023 contained 24 CCF entries across five WHO NPPM food categories, enabling CCF intake to be modelled across 48 scenarios spanning two sexes, six developmental ages and four dietary scenario targets. Across scenarios, CCFs contributed 22.7–28.1% of EER in Low, 47.5–52.9% in Medium and 70.5–77.8% in High scenarios, while Snack contributed 45.7–53.8% of EER. Free sugar contributions varied substantially across scenarios, with the Snack scenario contributing 29.4 and 34.0g/day among females and males aged 36 months, respectively. Sodium contributions were highest in the Snack scenario at ages 6 and 9 months, and in the High scenarios from 12–36 months for both sexes. In conclusion, AUSNUT 2023 provides a feasible basis for translating frequency and portion-size data derived from the novel dietary assessment tool into estimated nutrient intakes. However, uneven product representation and reliance on proxy foods may introduce measurement error. Comparison with a contemporary branded-food database is required to determine the robustness of nutrient estimates before national validation of the tool.