Drone Flight Time Calculator

Work out drone flight time instantly with clear inputs, formula shown and shareable results.

About Drone Flight Time Calculator

Flight time is usable battery capacity in amp-hours divided by average current draw. Lithium polymer packs should not be run flat, so only 75-85% of nameplate capacity is usable; that limit, not the raw mAh figure, sets the endurance you can plan on.

Formula

Drone endurance

time (min) = (capacity Ah x usable fraction / current draw) x 60

Worked example

With the default values below, Drone Flight Time Calculator returns Flight time of 13.33. Change any input above and every figure here is recalculated in your browser.

Inputs used

Battery capacity: 5,000 mAh
Battery voltage: 22.2 V
Average current draw: 18 A
Usable battery capacity: 80 %

Results

Flight time: 13.33 min
Usable energy: 88.80 Wh
Average power draw: 399.60 W
Reserve held back: 3.33 min

Step by step

1Values used
2Drone endurance
3Flight time= 13.33 min
4Usable energy= 88.80 Wh
5Average power draw= 399.60 W
6Reserve held back= 3.33 min

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Why not use the full capacity?

Discharging a LiPo below about 3.5 V per cell shortens its life sharply and risks a voltage sag that drops the aircraft. Landing with 20-25% remaining is standard practice.

Does a bigger battery always fly longer?

Not indefinitely. The extra mass raises hover current, so beyond an optimum pack size endurance starts to fall again.