BACKGROUND: The steep ramp test (SRT) is a feasible, reliable, and valid exercise test on a cycle ergometer that may be more appealing for use in children in daily clinical practice than the traditional cardiopulmonary exercise test, because of its short duration, its resemblance to children's daily activity pattern and the fact that it does not require respiratory gas analysis. OBJECTIVE: The aim of the current study was to provide sex- and age-related norm values for SRT performance in healthy Dutch Caucasian children and adolescents between the ages of 8 and 19 years. DESIGN: This was a cross-sectional, observational study. METHODS: Two hundred and fifty-two Dutch Caucasian children and adolescents, 118 boys (mean age 13.4 (3.0) years) and 134 girls (mean age 13.4 (2.9) years), performed a SRT (work rate increments of 10, 15, or 20 W·10 s(-1), depending on body height) to voluntary exhaustion to assess peak work rate (WRpeak). Norm values are presented as reference centiles developed using generalized additive models for location, scale, and shape (GAMLSS). RESULTS: WRpeak correlated highly with age (r=0.915 and r=0.811), body mass (r=0.870 and r=0.850), body height (r=0.922 and r=0.896), body surface area (r=0.906 and r=0.885), and fat free mass (r=0.930 and r=0.902), for boys and girls respectively (P<0.001 for all coefficients). The reference curves demonstrated an almost linear increase with age in WRpeak in boys, even when normalized for body mass. In contrast, absolute WRpeak in girls increased constantly until the age of approximately 13 years, where after WRpeak started to level off. WRpeak normalized for body mass showed only a slight increase with age in girls, with a slight decrease in relative WRpeak as of the age of 14 years. LIMITATIONS: The sample may not be entirely representative of the Dutch population. CONCLUSIONS: The current study provides sex- and age-related norm values for SRT performance for both absolute and relative WRpeak thereby facilitating the interpretation of SRT results for clinicians and researchers.