Objective: Low levels of daily energy expenditure (insufficient physical activity and increased sedentary time) have been associated with adverse health outcomes in young people. The Multimedia Activity Recall for Children and Adolescents (MARCA) is a computerized, self-report, use-of-time tool that can assess daily energy expenditure. The study aim was to validate the MARCA for the estimation of energy expenditure in young people, using the criterion standard doubly labeled water. Materials/Methods: Over a 15 day assessment period, 32 participants (10-18 years) completed the MARCA and underwent a doubly labeled water protocol. Indirect calorimetry was used to assess resting metabolic rate. Total daily energy expenditure (TEE) and activity-related energy expenditure (AEE) were estimated from both the MARCA and doubly labeled water. Association and agreement between methods for TEE and AEE were assessed using Spearman correlations and Bland-Altman plots, respectively. Results: Compared to doubly labeled water, the MARCA over-estimated TEE by an average of 50 kcal/day (limits of agreement - 1 589 to 1 490 kcal/day) and under-estimated AEE 105 kcal/day (limits of agreement - 1 404 to 1 614 kcal/day). The MARCA showed strong correlation with doubly labeled water for TEE (rho = 0.70, p < 0.0001) and moderate correlation for AEE (rho = 0.56, p = 0.0009). Conclusions: Overall, the MARCA indicated moderate validity for the assessment of daily TEE and AEE. The wide limits of agreement indicate the MARCA has greater utility for group-level rather than individual-level estimates.