Free Fall Calculator

What is the Free Fall Calculator?

Calculate fall time and impact velocity of an object dropped from a height (no air resistance). Free fall describes motion under gravity alone, and it shows how fall time and speed grow with height.

How to use the Free Fall Calculator

1. Enter your height, your gravity.
2. Results update automatically as you type; you can also press Calculate.
3. Read the output: fall time, impact velocity, impact velocity (km/h).
4. Use the 📊 chart to see the result visually, then copy or share it.

Formula and method

Worked example

With height = 20 m, gravity = 9.80665 m/s², the Free Fall Calculator returns fall time: 2.020 s; impact velocity: 19.806 m/s; impact velocity (km/h): 71.30 km/h.

Where the Free Fall Calculator helps in real life

You drop a stone from a 20 m bridge to estimate its height. Timing the fall and comparing it with the calculator’s result lets you check your estimate.

A student needs the impact speed of an object dropped from 5 meters. The calculator gives both time and velocity.

Common mistakes to avoid

• Ignoring air resistance for light objects.
• Using feet when the formula expects meters.
• Assuming time doubles when height doubles.
• Including reaction time in measured fall times.

💡 Practical tip: Doubling the height does not double the fall time — time grows with the square root of height.

Tips for better results

• Use the calculator for dense objects where air resistance matters less.
• Convert feet to meters before entering.
• Compare with measured times for experiments.

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