Time, speed and distance calculator
The other three sides of every flight-planning problem.
How it works
Time = distance ÷ groundspeed. Everything else on this page follows from that.
Reserves are not the target
The 45-minute figure shown is the IFR and night-VFR legal reserve; day VFR is 30 minutes. Both are the point below which you have broken a rule, not the point at which to start worrying. Pick a personal minimum — an hour is common — and treat reaching it as a decision, not a milestone.
Groundspeed, not airspeed
Use groundspeed here. If you only have true airspeed and a forecast wind, run the wind triangle first.
Other calculators
- Density altitude calculator
- Pressure altitude calculator
- True airspeed calculator
- Crosswind component calculator
- Wind correction angle and groundspeed calculator
- Cloud base calculator
- Top of descent calculator
- Climb gradient calculator
- Glide distance calculator
- Aviation unit converter
For planning and study, not for operational use. Aircraft performance comes from your POH, not from a generic formula.