How to Convert Nm to ft-lbs: Complete Torque Conversion Guide

Converting torque from Newton-meters (Nm) to foot-pounds (ft-lbs) is essential when working with international specifications or equipment from different regions. This guide provides everything you need for accurate conversions.

Quick Answer (TL;DR)

To convert Nm to ft-lbs:

ft-lbs = Nm × 0.737562

To convert ft-lbs to Nm:

Nm = ft-lbs × 1.35582

Example: 100 Nm = 100 × 0.737562 = 73.76 ft-lbs

Understanding Torque Units

What is a Newton-meter (Nm)?

Newton-meter is the SI (metric) unit for torque.

• 1 Nm = force of 1 Newton applied at 1 meter distance
• Used internationally in automotive and industrial applications
• Standard in European and Asian markets

Common Range:

• Small fasteners: 5-20 Nm
• Car wheel bolts: 80-140 Nm
• Engine components: 20-300 Nm

What is a Foot-pound (ft-lbs)?

Foot-pound is the imperial unit for torque.

• 1 ft-lb = force of 1 pound applied at 1 foot distance
• Dominant in United States
• Common in US automotive and construction

Common Range:

• Small fasteners: 4-15 ft-lbs
• Car wheel bolts: 60-100 ft-lbs
• Engine components: 15-220 ft-lbs

The Conversion Formula Explained

Nm to ft-lbs

ft-lbs = Nm × 0.737562

Where does 0.737562 come from?

This factor converts between metric and imperial systems:

• 1 Newton = 0.224809 pounds-force
• 1 meter = 3.28084 feet
• Therefore: 1 Nm = 0.224809 × 3.28084 = 0.737562 ft-lbs

ft-lbs to Nm

Nm = ft-lbs × 1.35582

Relationship:

• 1.35582 is the reciprocal of 0.737562
• 1 / 0.737562 = 1.35582

Step-by-Step Conversion Examples

Example 1: Wheel Lug Nuts

Given: Specification calls for 110 Nm

Convert to ft-lbs:

ft-lbs = 110 × 0.737562
ft-lbs = 81.13 ft-lbs

Practical value: 80-85 ft-lbs

Example 2: Spark Plugs

Given: US manual specifies 15 ft-lbs

Convert to Nm:

Nm = 15 × 1.35582
Nm = 20.34 Nm

Practical value: 20 Nm

Example 3: Oil Drain Plug

Given: European spec: 25 Nm

Convert to ft-lbs:

ft-lbs = 25 × 0.737562
ft-lbs = 18.44 ft-lbs

Practical value: 18-20 ft-lbs

Example 4: Cylinder Head Bolts

Given: 90 ft-lbs torque specification

Convert to Nm:

Nm = 90 × 1.35582
Nm = 122.02 Nm

Practical value: 120 Nm

Quick Reference Table

Common Torque Values

Torque Wrench Settings

Practical Applications

Automotive Maintenance

Common Torque Specifications:

Engine Components:

• Spark plugs: 15-25 Nm (11-18 ft-lbs)
• Oil drain plug: 20-30 Nm (15-22 ft-lbs)
• Oil filter: 15-20 Nm (11-15 ft-lbs)
• Valve cover bolts: 10-15 Nm (7-11 ft-lbs)
• Intake manifold: 15-25 Nm (11-18 ft-lbs)

Wheels and Brakes:

• Lug nuts (passenger car): 80-110 Nm (60-80 ft-lbs)
• Lug nuts (SUV/truck): 120-140 Nm (90-100 ft-lbs)
• Brake caliper bolts: 60-90 Nm (45-65 ft-lbs)
• Brake rotor screws: 10-15 Nm (7-11 ft-lbs)

Suspension:

• Control arm bolts: 80-120 Nm (60-90 ft-lbs)
• Shock absorber mounts: 60-80 Nm (45-60 ft-lbs)
• Sway bar links: 40-60 Nm (30-45 ft-lbs)

Bicycle Maintenance

Typical Torque Values:

Industrial Equipment

Heavy Machinery:

• Hydraulic fittings: 40-80 Nm (30-60 ft-lbs)
• Structural bolts: 200-400 Nm (150-300 ft-lbs)
• Flange bolts: 100-300 Nm (75-220 ft-lbs)

Torque Wrench Types and Conversion

Click-Type Torque Wrenches

Most common type, available in both units:

• Nm wrenches: Common in Europe, Asia
• ft-lbs wrenches: Common in US
• Dual-scale: Shows both units

Tip: If your wrench only shows one unit, use conversion before setting.

Digital Torque Wrenches

Advantages:

• Can switch between Nm and ft-lbs
• More accurate
• Often include memory functions

Example: Setting 80 Nm on digital wrench

1. Select Nm mode
2. Set to 80
3. Or switch to ft-lbs and set to 59

Beam-Type Torque Wrenches

Older style, often dual-scale:

• Read both Nm and ft-lbs simultaneously
• No conversion needed
• Less accurate than click or digital types

Important Considerations

Torque Specifications

Always use manufacturer specifications:

• Check service manual
• Verify torque sequence
• Follow tightening pattern
• Use correct torque angle if specified

Torque vs. Torque Angle

Some fasteners require:

1. Initial torque: e.g., 20 Nm (15 ft-lbs)
2. Plus angle: e.g., +90 degrees

Note: Angle is the same regardless of unit used for initial torque.

Dry vs. Lubricated Torque

Torque specifications may differ:

• Dry torque: Clean, unlubricated threads
• Lubricated torque: Oil or anti-seize applied

Typical difference: Lubricated = 70-80% of dry torque

Example:

• Dry spec: 100 Nm (74 ft-lbs)
• Lubricated: 70-80 Nm (52-59 ft-lbs)

Common Mistakes to Avoid

Mistake 1: Using Wrong Conversion Factor

❌ Wrong: Nm × 1.35582 = ft-lbs ✅ Right: Nm × 0.737562 = ft-lbs

Mistake 2: Confusing lb-in with ft-lbs

• lb-in (pound-inches): 1 ft-lb = 12 lb-in
• ft-lbs (foot-pounds): Standard torque unit

Example:

• 120 lb-in = 10 ft-lbs = 13.6 Nm

Mistake 3: Over-tightening

Converting and rounding up can lead to over-torque:

• 100 Nm = 73.76 ft-lbs
• ❌ Rounding to 75 ft-lbs = 101.7 Nm (too high!)
• ✅ Use 74 ft-lbs = 100.3 Nm (acceptable)

Mistake 4: Ignoring Torque Wrench Accuracy

Torque wrenches are typically accurate within:

• ±4% for quality wrenches
• ±6% for budget wrenches

Implication: Small conversion differences are often within tolerance.

Tools and Resources

Online Converters

• Nm to ft-lbs Converter
• ft-lbs to Nm Converter

Mobile Apps

Recommended torque conversion apps:

• Torque Converter Pro: iOS/Android
• Wrench Buddy: Android
• Torque Calc: iOS

Physical Tools

Torque Wrench Recommendations:

• Budget: $30-50 (click-type, single scale)
• Mid-range: $50-100 (click-type, dual-scale)
• Professional: $100-300 (digital, multiple units)

Frequently Asked Questions

Is Nm the same as N·m or N-m?

Yes, all represent Newton-meters:

• Nm (most common)
• N·m (with center dot)
• N-m (with hyphen)

What about kg-m (kilogram-meters)?

Older metric unit, rarely used now:

• 1 kg-m = 9.80665 Nm
• 1 kg-m = 7.23301 ft-lbs

Modern practice: Use Nm instead of kg-m.

Can I use a Nm wrench for ft-lbs specs?

Yes, just convert the specification:

• Spec: 80 ft-lbs
• Convert: 80 × 1.35582 = 108.5 Nm
• Set wrench to: 108 or 109 Nm

How precise do I need to be?

For most applications:

• ±5% is acceptable
• Critical applications: ±2%
• Torque-to-yield bolts: Follow exact specs

Conclusion

Converting between Nm and ft-lbs is straightforward with the right formulas:

Key Formulas:

• Nm to ft-lbs: Multiply by 0.737562
• ft-lbs to Nm: Multiply by 1.35582

Best Practices:

1. Always verify manufacturer specifications
2. Use a calibrated torque wrench
3. Follow proper tightening sequence
4. Consider lubrication effects
5. Round conservatively (don't over-torque)

For quick, accurate conversions:

• Nm to ft-lbs Converter
• ft-lbs to Nm Converter

Last Updated: January 22, 2026
Reading Time: 10 minutes