Free Drone Flight Time Calculator

Understanding Drone Flight Time

One of the most common questions among drone pilots is "How long can my drone fly?" This free online quadcopter flight time calculator—also a handy drone battery life calculator and hover time calculator—lets you input key parameters such as battery capacity, weight, voltage, and power draw to estimate the maximum hover duration and plan your flights accordingly.

The Core Formula

Flight time is determined by a simple relationship:

$$t = \frac{C \times D}{I_{\text{avg}}}$$

where:

• $t$ = flight time (in hours),
• $C$ = battery capacity (in amp‑hours, Ah; if your battery is rated in mAh, divide by 1000),
• $D$ = allowed depth of discharge (as a decimal, e.g., 0.80 for 80%),
• $I_{\text{avg}}$ = average current draw of the drone (in amperes).

LiPo batteries are typically discharged no more than 80% to avoid permanent damage. The tool uses 80% as the default, but you can change it if your battery supports a deeper discharge.

Estimating the Average Current Draw

If you do not know your drone’s average amp draw, you can compute it from weight and power requirements:

$$I_{\text{avg}} = \frac{W_{\text{total}} \times P}{V}$$

where:

• $W_{\text{total}}$ = all‑up weight (AUW) of the drone including the battery (in kg),
• $P$ = power required to lift one kilogram (in W/kg; a conservative default is 170 W/kg, efficient setups can use 120 W/kg),
• $V$ = battery voltage (in V).

Alternatively, if you know the current per kilogram ($I_{\text{per kg}}$), the formula reduces to:

$$I_{\text{avg}} = W_{\text{total}} \times I_{\text{per kg}}$$

Worked Example

Suppose you want a 30‑minute hover for aerial footage. Your battery is 8.8 Ah, voltage is 36 V, and the drone weighs 2.5 kg.

1. Discharge limit: 80% (0.80).
2. Power per kg: 170 W/kg.
3. Average current: $$I_{\text{avg}} = \frac{2.5 \times 170}{36} = 11.8\ \text{A}$$
4. Flight time: $$t = \frac{8.8 \times 0.80}{11.8} = 0.6\ \text{h} \approx 36\ \text{min}$$

The result gives enough margin to capture a 30‑minute video.

Real‑World Adjustments

The calculator assumes a hovering state. Actual flight time varies with flying style:

Flight scenario	Expected time vs. calculated
Hovering or gentle photo flights	~75%
Moderate wind or frequent maneuvers	~50%
FPV racing or sustained high throttle	25–30%

Aggressive maneuvers force motors to draw extra current, reducing endurance. Use these factors to set realistic expectations.

If you already know your drone’s average amp draw, you can enter it directly into the tool. The calculator also lets you adjust the discharge limit and the power‑per‑kilogram value to match your specific battery and propulsion system. Experiment with different combinations to answer "How long can my drone fly?" for any setup.