Torque Converter (N·m to lb-ft & in-lb)
Convert newton-meters to pound-feet for torque wrench settings, inch-pounds for small fasteners and kgf·m for older service manuals. Includes common tightening specs and step-by-step formulas.
Real-World Benchmarks
Multi-Unit Conversion Matrix
| Group | Measurement | Symbol | Equivalent Value |
|---|---|---|---|
| SI & Metric | Newton-Millimeter | N·mm | 100,000 |
| SI & Metric | Newton-Centimeter | N·cm | 10,000 |
| SI & Metric | Newton-Meter | N·m | 100 |
| SI & Metric | Kilonewton-Meter | kN·m | 0.1 |
| Imperial & US Customary | Pound-Foot | lbf·ft | 73.7562 |
| Imperial & US Customary | Pound-Inch | lbf·in | 885.0746 |
| Imperial & US Customary | Ounce-Inch | ozf·in | 14,161.1933 |
| Kilogram-force | Kilogram-Force Meter | kgf·m | 10.1972 |
| Kilogram-force | Kilogram-Force Centimeter | kgf·cm | 1,019.7162 |
Step-by-Step Mathematical Explanation
- 1 lbf·ft equals 1.35581794833 N·m, so divide by that factor: 100 ÷ 1.35581794833 = 73.756215 lbf·ft.
- Direct factor: 1 N·m = 0.73756215 lbf·ft.
Essential Conversion Factors
Newton-Meter: SI unit of torque — wrenches and engines
Quick Answer & Key Torque Formulas
Direct Answer: To convert newton-meters to pound-feet, multiply by 0.737562: lb·ft = N·m × 0.737562. To convert pound-feet to newton-meters, multiply by 1.355818: N·m = lb·ft × 1.355818. For inch-pounds, lb·in = N·m × 8.85075. One pound-foot equals 12 pound-inches.
Understanding Torque Units & Conversion Math
Torque is a force applied at a distance from a pivot. One newton-meter is one newton pushing on a one-meter lever; one pound-foot is one pound-force on a one-foot lever. Multiply the force factor (4.4482216 N per lbf) by the length factor (0.3048 m per ft) to get 1.355818 N·m per lb·ft.
1. Newton-Meters to Pound-Feet (N·m → lb·ft)
Divide by 1.355818 — or multiply by the reciprocal, 0.737562:
Example: 120 N·m × 0.737562 = 88.51 lb·ft.
2. Pound-Feet to Newton-Meters (lb·ft → N·m)
Multiply by the exact factor 1.3558179483:
Example: 100 lb·ft × 1.355818 = 135.58 N·m.
Torque Wrench Quick Scale
At the workbench, N·m is about 1.36 × lb·ft, and inch-pound specs are simply pound-feet × 12:
80 lb·ft ≈ 108 N·m (exact value: 108.47 N·m); 5 N·m = 44.25 lb·in.
Common Torque Specifications
| Application | N·m | lb·ft | Significance |
|---|---|---|---|
| Bike Stem Bolt | 5 | 3.7 (44 lb·in) | Carbon handlebar clamp |
| Spark Plug | 25 | 18.4 | 14 mm thread, aluminum head |
| Car Wheel Lug Nut | 110 | 81.1 | Typical passenger car spec |
| Cordless Impact Wrench | 200 | 147.5 | Compact 18 V tool rating |
| 2.0 L Turbo Engine | 350 | 258.1 | Peak engine torque |
| Heavy-Duty Diesel Pickup | 1,356 | 1,000 | Peak engine torque |
N·m to lb-ft Chart (Nm to ft-lbs)
| N·m | lbf·ft |
|---|---|
| 5 | 3.69 |
| 10 | 7.38 |
| 14 | 10.33 |
| 15 | 11.06 |
| 20 | 14.75 |
| 25 | 18.44 |
| 30 | 22.13 |
| 35 | 25.81 |
| 40 | 29.5 |
| 45 | 33.19 |
| 50 | 36.88 |
| 60 | 44.25 |
| 70 | 51.63 |
| 80 | 59 |
| 90 | 66.38 |
| 100 | 73.76 |
| 110 | 81.13 |
| 120 | 88.51 |
| 140 | 103.26 |
| 150 | 110.63 |
| 200 | 147.51 |
| 250 | 184.39 |
| 300 | 221.27 |
| 400 | 295.02 |
| 500 | 368.78 |
lb-ft to N·m Chart (ft-lbs to Nm)
| lbf·ft | N·m |
|---|---|
| 5 | 6.78 |
| 10 | 13.56 |
| 15 | 20.34 |
| 20 | 27.12 |
| 25 | 33.9 |
| 30 | 40.67 |
| 35 | 47.45 |
| 40 | 54.23 |
| 50 | 67.79 |
| 60 | 81.35 |
| 65 | 88.13 |
| 75 | 101.69 |
| 80 | 108.47 |
| 90 | 122.02 |
| 100 | 135.58 |
| 120 | 162.7 |
| 150 | 203.37 |
| 200 | 271.16 |
| 250 | 338.95 |
| 300 | 406.75 |
N·m to lb-in Chart (Nm to in-lbs)
| N·m | lbf·in |
|---|---|
| 0.5 | 4.43 |
| 1 | 8.85 |
| 1.5 | 13.28 |
| 2 | 17.7 |
| 2.5 | 22.13 |
| 3 | 26.55 |
| 4 | 35.4 |
| 5 | 44.25 |
| 6 | 53.1 |
| 8 | 70.81 |
| 10 | 88.51 |
| 12 | 106.21 |
| 15 | 132.76 |
| 20 | 177.01 |
| 25 | 221.27 |
Frequently Asked Questions
What is the difference between torque and power?
Torque is the twisting force an engine produces; power is torque multiplied by rotational speed. hp = lb·ft × rpm ÷ 5,252, which is why hp and lb·ft curves always cross at 5,252 rpm.
Is it ft-lb or lb-ft?
Both are used. Engineers prefer lb·ft (pound-feet) for torque and ft·lb (foot-pounds) for work or energy, but torque wrenches and service manuals often write ft-lb. The numeric value is the same.
Is a newton-meter the same as a joule?
Dimensionally yes (both are N × m), but by convention N·m is used for torque and the joule for energy. Torque is a vector twisting moment; energy is scalar work done.
How do I convert kgf·m to N·m?
Multiply by standard gravity, 9.80665: 10 kgf·m = 98.07 N·m. Older Japanese and European manuals often list torque in kgf·m or kgf·cm.