This site is being decommissioned. The legacy site may become unstable or unavailable at any time.
After more than 20 years of serving the pediatric cardiology community, the Parameter(z) calculators have moved to a new home at Rady Children's Hospital. The new site includes all the familiar calculators with modern features and ongoing support.
New Site (Recommended): Fully functional with all calculators, modern interface, and continued maintenance.
Legacy Site: No longer maintained after January 31, 2026. May become unstable, unreliable, or completely unavailable at any time. Final shutdown by January 2027.
Warning: These calculators are no longer maintained and may become unavailable at any time:
For questions about the new Rady site or to report calculator issues, please use the "Report an Issue/Request a Feature" link on the Rady Children's Hospital site.
For questions about the history of this project, reference sources, or general z-score methodology, feel free to reach out to me on LinkedIn: