Inch Lbsto Nm Converter
Convert inch lbsto nm between units instantly. Includes conversion tables, common equivalents, and calculation formulas.
Reviewed by Manoj Kumar, Mathematics Educator
Formula
Nm = inch-pounds x 0.112985
Multiply the torque value in inch-pounds by 0.112985 to get newton-meters. This factor comes from 1 lbf = 4.44822 N and 1 inch = 0.0254 m, so 1 in-lb = 4.44822 x 0.0254 = 0.112985 Nm. To convert back, divide newton-meters by 0.112985.
Worked Examples
Example 1: Converting a Small Bolt Torque Spec
Problem:A service manual specifies tightening a screw to 25 inch-pounds. What is this in newton-meters?
Solution:Nm = inch-pounds x 0.112985\nNm = 25 x 0.112985 = 2.8246 Nm\nft-lbs = 25 / 12 = 2.0833 ft-lbs
Result:25 in-lbs = 2.8246 Nm = 2.0833 ft-lbs
Example 2: Converting Nm Back to Inch-Pounds
Problem:A European bicycle manual says to torque a stem bolt to 5 Nm. What is that in inch-pounds?
Solution:in-lbs = Nm / 0.112985\nin-lbs = 5 / 0.112985 = 44.2537 in-lbs\nft-lbs = 44.2537 / 12 = 3.6878 ft-lbs
Result:5 Nm = 44.2537 in-lbs = 3.6878 ft-lbs
Frequently Asked Questions
What is the conversion factor from inch-pounds to newton-meters?
One inch-pound is equal to exactly 0.112985 newton-meters. This conversion factor is derived from the definition of a pound-force (approximately 4.44822 newtons) and an inch (0.0254 meters). Multiplying these together gives 4.44822 times 0.0254, which equals 0.112985 Nm per in-lb. This factor is widely used in automotive and mechanical engineering when converting torque specifications between imperial and metric systems.
When would I need to convert inch-pounds to newton-meters?
This conversion is commonly needed when working with torque wrenches or fastener specifications from different countries. American-made tools and manuals typically list torque values in inch-pounds or foot-pounds, while European and Asian manufacturers use newton-meters. Automotive mechanics, bicycle technicians, and electronics assemblers frequently need this conversion when following service manuals that use a different unit system than their available tools.
What is the difference between inch-pounds and foot-pounds?
Both are imperial units of torque, but they differ in scale. One foot-pound equals exactly 12 inch-pounds, since there are 12 inches in a foot. Inch-pounds are used for smaller, more delicate torque applications such as electronics screws, small engine components, and precision assemblies. Foot-pounds are used for larger fasteners like automotive lug nuts, cylinder head bolts, and structural connections where higher torque values are required.
References
Reviewed by Manoj Kumar, Mathematics Educator · Editorial policy