When to use this calculator
Estimate fall time from rest under constant gravity without air resistance. Ignores air resistance and assumes zero initial vertical velocity.
Explore the motion & kinematics calculators for other questions in this topic. For a related calculation, use the Horizontal Projectile Range Calculator: Find horizontal travel before an ideal horizontally launched object reaches the ground.
PUTTING IT INTO PRACTICE
Free Fall Time: a worked example
The values below are an illustrative example, not a recommendation. Replace them with measurements or assumptions that match your question.
| Input | Example value |
|---|---|
| Fall height (m) | 20 |
| Gravity (m/s²) | 9.80665 |
| Result | 2.01962 seconds |
- Check the input labels and enter the example values above.
- Apply the relationship: Time = √(2 × height ÷ gravity).
- The result is 2.01962 seconds, rounded for display.
How to interpret your result
Ignores air resistance and assumes zero initial vertical velocity.
Choose a reference direction before using signed velocities. Constant-acceleration models do not capture variable braking or drag. Projectile tools explicitly state launch and landing assumptions.
Frequently asked questions
Are displacement and distance interchangeable?
No. Displacement is the signed or directed change in position; distance counts the length of the path travelled.
How do I use the free fall time calculator?
Enter fall height (m), gravity (m/s²). The result updates automatically. Use the units shown beside each input; the example values illustrate the method.
Which formula does this calculator use?
Time = √(2 × height ÷ gravity).
What should I check before using the result?
Ignores air resistance and assumes zero initial vertical velocity.
How are results rounded?
Scalar numbers display up to six decimal places, with scientific notation for very large or small values. Text, fraction, date and schedule outputs use the format described on the tool. Intermediate calculations use JavaScript floating-point arithmetic. Keep sensible precision for your measurements.
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