How to use it
- Enter specific impulse in seconds.
- Enter positive initial and final masses, with final mass lower.
- Calculate ideal delta-v.
Rocket Equation Calculator
Apply the ideal rocket equation to three entered numerical values.
Important: This calculator is an educational estimate only. It is not aviation, navigation, flight planning, fuel or reserve planning, aircraft or rocket design, certification, launch, propulsion, mission, weapon, maintenance, legal, regulatory, emergency, operational, or safety advice.
About the Rocket Equation Calculator
The ideal rocket equation relates entered specific impulse and mass ratio to a theoretical velocity change.
Formula
Δv = Isp × g0 × ln(m0 ÷ mf), using g0 = 9.80665 m/s².
Example
Isp 300 s, initial mass 50,000 kg and final mass 20,000 kg gives an ideal delta-v near 2.70 km/s.
Notes
Gravity losses, drag, staging, structure, trajectory and propulsion limits are excluded. This is not launch, mission, weapon, design or safety guidance.