Terminal velocity and falling objects
Compare a falling object’s speed with air resistance and ideal vacuum free fall. Drag the graph handles to change inputs and explore the result.
Your inputs
The editable example is illustrative. Enter your own dimensions, operating data, prices, and fees. Results update as you edit.
Calculations run in your browser. Inputs are not saved or sent to analytics.
How it works
- vₜ = √(2 / ()); v() = vₜ tanh(/vₜ); () = (vₜ²/) ln(cosh(/vₜ)); v₀() =
Input and formula key
Your result
Complete the inputs to see your result.
Assumptions and limitations
Vertical release from rest, quadratic air drag, fixed density, area, drag coefficient and gravity. Buoyancy, wind, tumbling, compressibility and altitude changes are excluded; this is an educational model. Height mode compares impacts at the same height; the graph compares speeds at the same elapsed time. Example: 1 kg, 1 m², Cd=1, air density 1.225 and g=9.80665 give terminal speed ≈4.00136 m/s.
Sources
- NASA Glenn — falling objects with air resistance Sources reviewed: 2026-10-21
- NASA Glenn — motion with quadratic drag Sources reviewed: 2026-10-21
