Torque Calculator from Rpm

Torque Formula:

\[ Torque = \frac{HP \times 5252}{RPM} \]

Torque:

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is Torque?

Torque is a measure of rotational force, representing how much force is acting on an object to make it rotate. In automotive terms, it's the twisting force that the engine generates.

2. How Does the Calculator Work?

The calculator uses the torque formula:

\[ Torque = \frac{HP \times 5252}{RPM} \]

Where:

\( Torque \) — Rotational force (lb-ft)
\( HP \) — Horsepower (hp)
\( RPM \) — Rotations per minute (rev/min)
5252 — Conversion constant (derived from the relationship between horsepower, torque, and RPM)

Explanation: The constant 5252 comes from the fact that 1 horsepower is defined as 550 foot-pounds per second, and there are 2π radians in a revolution.

3. Importance of Torque Calculation

Details: Torque is crucial in understanding an engine's performance characteristics. High torque at low RPMs provides better acceleration from a stop, while high torque across a broad RPM range indicates strong overall performance.

4. Using the Calculator

Tips: Enter horsepower in hp and RPM in rev/min. All values must be valid (HP > 0, RPM > 0).

5. Frequently Asked Questions (FAQ)

Q1: Why is 5252 RPM special in torque calculations?
A: At 5252 RPM, horsepower and torque values are always equal (when using lb-ft and hp units) due to the mathematical relationship between the two.

Q2: What's the difference between horsepower and torque?
A: Torque measures rotational force, while horsepower measures the rate at which work is done (torque × RPM). Horsepower determines top speed, while torque determines acceleration.

Q3: How does gearing affect torque?
A: Gearing can multiply torque at the wheels (at the expense of RPM) or increase RPM (at the expense of torque), but doesn't change the engine's actual torque output.

Q4: What's a typical torque value for a car?
A: Typical passenger cars might have 100-200 lb-ft, while performance cars can have 300-500 lb-ft or more. Diesel engines often produce higher torque at lower RPMs.

Q5: Can I calculate horsepower if I know torque and RPM?
A: Yes, using the formula: \( HP = \frac{Torque \times RPM}{5252} \)