# Drone Motor Calculator (Thrust per Motor)

URL: https://speedycalculator.com/calculators/other/drone-motor/
Last updated: 2026-10-30

> The drone motor calculator finds the total thrust and the thrust each motor must produce from the drone's all-up weight – entered directly or as frame, battery and payload weights – the thrust-to-weight ratio you want and the number of motors.

## Inputs

- Weight input
- Frame, motors, propellers and electronics (g, kg, oz, lb)
- Battery (g, kg, oz, lb)
- Payload (camera, gimbal, other equipment) (g, kg, oz, lb)
- Total (all-up) weight (g, kg, oz, lb)
- Thrust-to-weight ratio (: 1) — 2:1 gentle flying, 3:1 all-round, 4–5:1 FPV, 7:1 and up for acrobatics.
- Number of motors

## Results

- All-up weight
- Total thrust needed
- Thrust needed per motor
- Thrust per motor to hover
- Approximate hover throttle
- Suitable for

## Formula

```
Total thrust = all-up weight × thrust-to-weight ratio · thrust per motor = total thrust ÷ number of motors · hover throttle ≈ 1 ÷ ratio
```

## Explanation

Choosing motors and propellers for a multirotor starts with thrust. To hover, the motors together must lift the whole drone; to climb, turn and fight wind they need a reserve. Builders express that reserve as the thrust-to-weight ratio: at 2:1 the motors can produce twice the drone's weight, so it hovers at about half throttle.

A ratio of 2:1 is the minimum for a stable, controllable aircraft such as a camera or mapping drone. Around 3:1 gives a lively all-rounder, 4:1–5:1 suits FPV freestyle and racing, and acrobatic racers reach 7:1 or more. Too low a ratio leaves no headroom for gusts or for the battery's voltage dropping late in a flight; too high a ratio wastes weight and makes the drone twitchy at low throttle.

Motor makers publish thrust tables – grams of thrust at full throttle for a given propeller and battery voltage. Pick a motor and propeller combination whose maximum thrust meets or exceeds the per-motor figure here. Remember that the motors themselves add weight: if you change to heavier motors, add their weight and check again.

### How to use the Drone Motor Calculator

- **Weight input**
- **Frame, motors, propellers and electronics**
- **Battery**
- **Payload (camera, gimbal, other equipment)**
- **Total (all-up) weight**
- **Thrust-to-weight ratio** — 2:1 gentle flying, 3:1 all-round, 4–5:1 FPV, 7:1 and up for acrobatics.
- **Number of motors**

Results update as you type, every field has its own unit menu, and everything is calculated in your browser.

### How it works

Enter the weight of the frame and electronics, the battery and the payload (or the total), choose the thrust-to-weight ratio and the number of motors. The calculator adds the weights, multiplies by the ratio and divides by the motor count.

### Worked example

A quadcopter has a 500 g frame with motors and electronics, a 150 g battery and a 50 g camera: 700 g in total. At a 3:1 ratio the motors must produce 2,100 g together, or **525 g per motor**. If heavier motors add 15 g in total, the weight becomes 715 g and each motor needs 715 × 3 ÷ 4 = 536 g.

### Recommended ratios

UseThrust-to-weightHover throttleCamera, mapping, heavy lift2:1≈ 50%All-round hobby3:1≈ 33%FPV freestyle4:1–5:120–25%Racing, acrobatics7:1 and up< 15%

### Inputs explained

FieldWhat to enterWeight inputChoose one: Add up the parts, I know the total weightFrame, motors, propellers and electronicsUnits: g, kg, oz, lbBatteryUnits: g, kg, oz, lbPayload (camera, gimbal, other equipment)Units: g, kg, oz, lbTotal (all-up) weightUnits: g, kg, oz, lbThrust-to-weight ratioIn : 1. 2:1 gentle flying, 3:1 all-round, 4–5:1 FPV, 7:1 and up for acrobatics.Number of motorsChoose one: 3 – tricopter, 4 – quadcopter, 6 – hexacopter, 8 – octocopter

### What each result means

- **Total thrust needed** = [All-up weight]×[Thrust-to-weight ratio]
- **Thrust needed per motor** = [Total thrust needed]÷[Number of motors]
- **Thrust per motor to hover** = [All-up weight]÷[Number of motors]
- **Approximate hover throttle** = 100÷[Thrust-to-weight ratio]

## Worked example

Inputs — Weight input: Add up the parts; Frame, motors, propellers and electronics: 500 g; Battery: 150 g; Payload (camera, gimbal, other equipment): 50 g; Thrust-to-weight ratio: 3 : 1; Number of motors: 4 – quadcopter.

Results — All-up weight = 700 g; Total thrust needed = 2,100 g; **Thrust needed per motor = 525 g**; Thrust per motor to hover = 175 g; Approximate hover throttle = 33.3 %; Suitable for = Agile all-round flying (3:1).

## Key terms

- **Thrust-to-weight ratio**: Maximum total thrust divided by the drone's weight.
- **All-up weight**: Total flying weight including battery and payload.
- **Hover throttle**: Throttle setting at which thrust equals weight.
- **Thrust table**: Manufacturer data of thrust, current and power for a motor and propeller.

## FAQ

**What thrust-to-weight ratio does a drone need?**
At least 2:1; 3:1 for agile flying, 4:1–5:1 for FPV freestyle and racing.

**How much thrust does each motor need?**
Total weight × ratio ÷ motors – a 700 g quad at 3:1 needs 525 g per motor.

**Why is a ratio of 1:1 not enough?**
The drone could only just hover at full throttle, leaving nothing for control, climbing or wind.

**How do I read a motor thrust table?**
Find the row for your propeller and battery voltage; the full-throttle thrust in grams must exceed the per-motor value.

**Does adding motors increase efficiency?**
Not necessarily – more motors add redundancy (hexa/octo) but also weight; larger propellers on fewer motors are usually more efficient.

**How does hover throttle relate to the ratio?**
Roughly hover throttle ≈ 1 ÷ ratio, so 2:1 hovers near 50% and 4:1 near 25%.


## Sources

- [Thrust-to-weight ratio – Wikipedia](https://en.wikipedia.org/wiki/Thrust-to-weight_ratio)
- [Quadcopter – Wikipedia](https://en.wikipedia.org/wiki/Quadcopter)