OBJECTIVE: To assess frailty, a measure of physiologic declines in multiple organ systems, in children with chronic liver disease using a novel pediatric frailty tool. STUDY DESIGN: We performed a prospective cross-sectional multicenter study at 17 liver transplantation (LT) centers. 71 children (5-17 years of age), 36 with compensated chronic liver disease (CCLD) and 35 with end-stage liver disease (ESLD) and listed for LT, were assessed for frailty using validated pediatric tools to assess the 5 classic Fried Frailty Criteria-slowness, weakness, exhaustion, diminished physical activity, and shrinkage. Test scores were translated to age- and sex-dependent z scores, generating a maximum frailty score of 10. RESULTS: The median frailty score of the cohort was 4 (IQR 3, 5). Subjects with ESLD had significantly higher frailty scores (median 5; IQR 4, 7) than subjects with CCLD (median 3; IQR 2, 4); (P < .0001). Area under the curve receiver operating characteristic for frailty scores to discriminate between ESLD and CCLD was 0.83 (95% CI 0.73, 0.93). Forty-six percent of children with ESLD were frail and there was no correlation between pediatric frailty scores and physician's global assessments (r = -0.24, 95% CI -0.53, 0.10). CONCLUSIONS: A novel frailty tool assessed additional dimensions of health, not captured by standard laboratory measures and identified the sickest individuals among a cohort of children with chronic liver disease. This tool may have applicability to other children with chronic disease.