Horizontal Distance Calculator

Summary

Enter slope distance and vertical angle (or zenith angle) to instantly compute horizontal distance, vertical difference, and gradient.

How it works

1. Enter the slope distance — the measured length along the line of sight (e.g., from a total station to a prism).
2. Select the angle type: Elevation Angle (up/down from horizontal), Zenith Angle (down from vertical), or Gradient.
3. Enter the angle or gradient value in the provided field.
4. Click Calculate to get horizontal distance, vertical difference, gradient ratio, and gradient percentage.
5. Use the visual diagram to confirm the geometry of your triangle.
6. Click Reset to clear all fields and start a new calculation.

Use cases

• Reducing total station slope distance readings to horizontal map distances.
• Trigonometric leveling — computing height difference between two survey points.
• Converting EDM (Electronic Distance Measurement) slope readings for field books.
• Checking horizontal distance when working with inclined boreholes or drill holes.
• Road and railway design: computing horizontal run from measured slope chainage.
• Mine surveying: reducing slope shots to horizontal and vertical components.
• GPS / GNSS height difference verification against total station shots.
• Educational use: demonstrating applied trigonometry for surveying students.

Frequently Asked Questions