Flat vs Round Earth Calculator

Compare scientific predictions between flat and spherical Earth models. Calculate horizon distances, curvature effects, and explore real-world evidence with our educational tool designed for learning and discovery.

  • Educational Tool
  • Scientific Evidence
  • Real-time Calculations
  • Mobile Optimized

Enter observer parameters for Earth model comparison

Tip: Try different scenarios using the preset buttons below.

Enter the height of the observer above ground level in feet.
Enter the height of the target object in feet.
Enter the distance to the target object in miles.
Select atmospheric refraction coefficient based on weather conditions.
Maintained by Toolexe Last updated September 30, 2026