EV Motor Torque Calculator
Calculate electric motor torque, wheel torque, and vehicle acceleration for EV applications
Formula
Motor Torque:
$$T_{motor} = \frac{P \times 60}{2\pi \times RPM} \times 1000$$
Wheel Torque & Tractive Force:
$$T_{wheel} = T_{motor} \times G_{ratio}$$
$$F_{tractive} = \frac{T_{wheel}}{r_{wheel}}$$
Acceleration:
$$a = \frac{F_{tractive}}{m}$$
About this Calculator
This calculator helps you analyze electric motor performance for EV applications. Calculate motor torque from power and RPM, then see how gear ratio and wheel size affect wheel torque, tractive force, and vehicle acceleration.
How to Use
- Enter your motor's peak power in kW
- Set the motor RPM at which you want to calculate torque
- Enter the transmission gear ratio (single-speed EVs typically 8-10:1)
- Set the wheel diameter including tire (commonly 600-700mm)
- Enter the total vehicle mass including passengers
- View motor torque, wheel torque, and acceleration estimates
Frequently Asked Questions
What gear ratio do EVs typically use?
Most single-speed EVs use ratios between 8:1 and 10:1. Tesla Model 3 uses 9:1, Porsche Taycan uses a 2-speed with 16:1 and 8.05:1. Higher ratios give more torque multiplication but lower top speed.
Why is EV acceleration so fast?
Electric motors provide instant maximum torque from 0 RPM, unlike combustion engines that need to rev up. Combined with high gear ratios and no shift interruptions, EVs can achieve remarkable acceleration.
How does wheel size affect performance?
Larger wheels reduce effective gear ratio (less torque multiplication) but increase top speed. Smaller wheels give better acceleration but lower top speed. Most EVs use 18-21 inch wheels (650-750mm total diameter with tire).
