How to use the distance to the horizon calculator
Estimate how far you can see across the sea or flat land from your eye height. Enter observer height in the field above; the distance to horizon are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “distance to horizon”, “how far can I see”, “horizon distance from height”, “calculate distance to the horizon”, “find distance to horizon”.
Formula
Variables
- h — Observer height (m)
Worked example
With observer height = 1.7 m, the calculator gives distance to horizon ≈ 4.654181 km; distance to horizon ≈ 2.891973 miles.
Frequently asked questions
What is the distance to the horizon calculator used for?
Estimate how far you can see across the sea or flat land from your eye height. It helps with questions such as “distance to horizon”, “how far can I see”, “horizon distance from height”.
What is the formula for the distance to the horizon calculation?
Distance to horizon (km) = √(2 × REARTH × h) / 1000. Distance to horizon (miles) = [Distance to horizon] × 0.621371. Here h is observer height (m).
What inputs do I need for the distance to the horizon calculator?
You need observer height in m. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the distance to the horizon calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the distance to the horizon result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.