🔄 Converters
🔧 🔧 Torque Converter: Nm, lb-ft, and kg-cm Explained
Learn how to convert torque between Newton-meters, pound-feet, and kilogram-centimeters. Covers what torque is, the conversion formulas, and real-world torque reference values.
⏱️ 7 min read🦉 365tool.net🌍 For everyone worldwide
Torque is the rotational equivalent of force — it measures how much twisting force is applied to an object around an axis. It appears in engine specifications, fastener tightening instructions, bicycle bottom brackets, and any mechanical system involving rotation. The US uses pound-feet (lb-ft), most of the world uses Newton-meters (Nm), and some engineering contexts use kilogram-force centimeters (kgf·cm).
What Is Torque?
Torque = Force × Distance from the pivot point
When you use a wrench to tighten a bolt, torque = the force you apply × the wrench length. A longer wrench produces more torque for the same applied force — this is why breaker bars exist. Torque is a vector quantity: its direction (clockwise vs counterclockwise) matters as much as its magnitude.
Torque Units
- Newton-meter (Nm): SI standard. 1 Nm = 1 N of force applied 1 m from the pivot. Used globally in automotive specs outside the US.
- Pound-foot (lb-ft): US standard. 1 lb-ft = 1 pound of force applied 1 foot from the pivot. Common in US automotive, aerospace, and construction.
- Pound-inch (lb-in): 1 lb-ft = 12 lb-in. Used for smaller fasteners and precision work.
- Kilogram-force centimeter (kgf·cm): Older metric unit still found in some specifications. 1 kgf·cm = the torque produced by 1 kg of weight acting 1 cm from the pivot.
Conversion Formulas
| Convert |
Multiply by |
Example |
| Nm → lb-ft | × 0.73756 | 100 Nm = 73.76 lb-ft |
| lb-ft → Nm | × 1.35582 | 100 lb-ft = 135.58 Nm |
| Nm → kgf·m | × 0.10197 | 100 Nm = 10.20 kgf·m |
| kgf·m → Nm | × 9.80665 | 10 kgf·m = 98.07 Nm |
| lb-ft → lb-in | × 12 | 5 lb-ft = 60 lb-in |
Real-World Torque Reference Values
| Application |
Nm |
lb-ft |
| Bicycle bolt (stem) | 4–6 | 3–4 |
| Spark plug | 20–30 | 15–22 |
| Wheel lug nut | 80–120 | 59–89 |
| Compact car engine (peak) | 150–200 | 111–148 |
| Performance sedan (peak) | 350–500 | 258–369 |
| Heavy diesel truck engine | 1,500–2,500 | 1,106–1,843 |
Torque vs Power
Torque and power are related but different. Torque is twisting force (how hard the engine pulls). Power (horsepower or kW) is how fast torque is delivered:
Power (kW) = Torque (Nm) × RPM ÷ 9,549
Power (hp) = Torque (lb-ft) × RPM ÷ 5,252
High torque at low RPM = good for towing and acceleration from low speed (diesel engines, electric motors). High power at high RPM = good for top speed (petrol engines at redline). Electric vehicles produce peak torque instantly from 0 RPM, which is why they feel fast off the line.
❓ Frequently Asked Questions
How do I convert Newton-meters to pound-feet?▼
Multiply Nm by 0.73756. Examples: 100 Nm = 73.76 lb-ft; 200 Nm = 147.5 lb-ft; 400 Nm = 295 lb-ft. For the reverse (lb-ft to Nm): multiply by 1.35582. A wheel lug nut torqued to 100 Nm = 73.76 lb-ft.
What is torque in simple terms?▼
Torque is rotational force — how hard something is twisted around an axis. Using a wrench: torque = force applied × wrench length. A 10 N force on a 0.3 m wrench produces 3 Nm of torque. A longer wrench creates more torque for the same effort, which is why breaker bars help with stubborn bolts.
What is the difference between torque and horsepower?▼
Torque is the twisting force an engine produces. Power (horsepower or kW) is how quickly that torque is delivered — it depends on both torque and RPM. Power = Torque × RPM ÷ 5,252 (for hp with lb-ft). High torque at low RPM (diesel, electric) gives strong pulling power. High power at high RPM (petrol sports engines) gives top speed.
What torque should I use to tighten lug nuts?▼
Most passenger car wheel lug nuts require 80–120 Nm (59–89 lb-ft). Always check your vehicle's owner manual for the exact specification — under-torquing risks the wheel coming loose; over-torquing can stretch or break studs. Use a calibrated torque wrench and tighten in a star pattern.
Why do electric vehicles have high torque?▼
Electric motors produce maximum torque from 0 RPM because they don't need to build up speed to generate force — electromagnetic torque is instantaneous. Internal combustion engines build torque as RPM rises, reaching peak torque at a specific RPM band. This is why EVs feel very fast from a standstill despite sometimes lower peak power than equivalent petrol cars.