how far can you see to the horizon

Standing at the beach with your eyes about 1.7–1.8 m above the water, the geometric horizon is roughly 4.5–5 km away; if you get much higher (like a mountain or tall building), it can extend to hundreds of kilometers.

Basic idea

The distance to the horizon is set mostly by two things:

• The curvature of Earth
• How high your eyes are above the surface

On a perfectly flat sea with clear air, a person of average height (around 1.7–1.8 m eye level) can see the horizon at about 4.5–4.8 km away.

Handy rule of thumb

For eye height hhh in metres above the surface, a widely used approximation for distance to the horizon ddd in kilometres is:

• d≈3.57hd\approx 3.57\sqrt{h}d≈3.57h​ to 3.6h3.6\sqrt{h}3.6h​ km.

Examples.

• Eye level 1.5 m: horizon ≈ 4.4 km.

• Eye level 1.8 m: horizon ≈ 4.8 km.

From higher places

As you go higher, the distance grows with the square root of your height, so it increases quickly but not linearly.

Typical values often quoted:

• 30 m cliff or tower: horizon ≈ 19–20 km.

• 100 m high: horizon ≈ 36 km.

• Top of Burj Khalifa (~834 m above sea level): horizon ≈ 103 km.

• Summit of Mount Everest (~8848 m): horizon ≈ 330–370 km.

Why it’s only an approximation

In real life, what you can see is affected by:

• Atmospheric refraction slightly bending light, usually extending the effective horizon a bit.

• Weather, haze, and air clarity, which often limit visibility well before the geometric horizon.

Information gathered from public forums or data available on the internet and portrayed here.