Use the 3-Blade to 4-Blade Propeller Calculator to compare thrust, speed, and efficiency. Find the right blade setup for your boat’s performance goals.
Propeller Conversion Results
Project: | Application:
| Metric | 3-Blade Propeller | 4-Blade Propeller |
|---|---|---|
| Static Thrust | ||
| Dynamic Thrust | ||
| Power Output | ||
| Thrust per Power | ||
| Torque | ||
| Current Draw |
Show unit definitions
Metric Units:
- Newtons (N): Unit of force (1 N ≈ 0.225 lbf)
- Watts (W): Unit of power (1 W ≈ 0.00134 hp)
- Newton-meters (N·m): Unit of torque (1 N·m ≈ 0.738 ft·lb)
- Amperes (A): Unit of electrical current
- Pounds-force (lbf): Unit of force (1 lbf ≈ 4.448 N)
- Horsepower (hp): Unit of power (1 hp ≈ 745.7 W)
- Foot-pounds (ft·lb): Unit of torque (1 ft·lb ≈ 1.356 N·m)
- Amperes (A): Unit of electrical current
Understanding Your Results
- Static Thrust: The force your propeller generates when the vehicle is stationary. Higher thrust means better acceleration or lift (e.g., for drones).
- Dynamic Thrust: The force when moving at the specified speed. Only shown if you enter a velocity greater than 0.
- Power Output: The energy the propeller delivers. More power means more energy consumption, affecting battery life or fuel use.
- Thrust per Power: How efficiently the propeller converts power into thrust. Higher is better, meaning more thrust for less power.
- Torque: The twisting force needed to spin the propeller. Higher torque may strain your motor, requiring a stronger one.
- Current Draw: The electrical current your motor uses. Higher current can drain batteries faster or require a larger power system.
Typical Propeller Performance
| Application | Blades | Thrust Range (N) | RPM Range |
|---|---|---|---|
| Air – Drone | 3 | 5–50 | 8000–20000 |
| Air – Drone | 4 | 6–60 | 8000–20000 |
| Air – RC Plane | 3 | 10–100 | 6000–15000 |
| Air – RC Plane | 4 | 12–120 | 6000–15000 |
| Water – Inboard | 3 | 1000–10000 | 1000–3000 |
| Water – Inboard | 4 | 1200–12000 | 1000–3000 |
| Water – Outboard | 3 | 500–5000 | 2000–6000 |
| Water – Outboard | 4 | 600–6000 | 2000–6000 |
| Water – Sterndrive | 3 | 800–8000 | 1500–4000 |
| Water – Sterndrive | 4 | 950–9500 | 1500–4000 |
Note: Results are estimates based on simplified models. Test propellers in real conditions for accurate performance.
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