Convert Torque from Pound-inches to Centinewton-meters (lbf-in to cNm)

Pound-inch to Centinewton-meter Conversion Formula

Example

Let's convert 5 Pound-inch (lbf-in) to Centinewton-meter (cNm).

Using the formula:

Therefore, 5 Pound-inch (lbf-in) is equal to 56.492416666666666665 Centinewton-meter (cNm).

How many pound-inches are in one centinewton-meter? One Centinewton-meter (cNm) contains 0.088507454540358661708 Pound-inches (lbf-in) — the inverse of the factor above. Multiplying by 11.298483333333333333 takes you from pound-inches to centinewton-meters; multiplying by 0.088507454540358661708 brings you back.

Put in words: one pound-inch equals 11.298483333333333333 centinewton-meters, so the pound-inch is the larger unit of this pair. Converting between them never changes the amount of torque being measured — only the size of the unit you count it in.

What Is a Pound-inch (lbf·in)?

A pound-inch (lbf·in) is one pound-force applied at one inch from the axis of rotation. It is the small-torque companion to the pound-foot.

• 1 lbf·ft = 12 lbf·in (exactly, since a foot is twelve inches)
• 1 lbf·in = 0.112985 N·m

Why a Smaller Imperial Unit Exists

Many fasteners are tightened to far less than one pound-foot. Writing "0.4 lbf·ft" invites a decimal-point error on a shop floor; writing "5 lbf·in" does not. Small-torque work therefore uses inch units almost exclusively.

Where Pound-inch Is Used

• Electrical terminals — breaker lugs and terminal blocks are specified in lbf·in, and both under- and overtightening cause failures.
• Electronics and instrument assembly — small screws in enclosures and connectors.
• Aerospace fasteners — small-diameter hardware throughout aircraft assembly.
• Optics, firearms and precision equipment — mounting screws where excess torque distorts the assembly.

Torque screwdrivers and small click wrenches are graduated in lbf·in for exactly this range.

A Common and Expensive Mistake

Confusing lbf·in with lbf·ft applies twelve times the intended torque. On a 5 lbf·in electrical terminal this shears the screw or crushes the conductor. Always check which unit the specification uses before setting a wrench.

Converting Pound-inch

What Is a Centinewton-meter (cN·m)?

A centinewton-meter (cN·m) is one hundredth of a newton-meter — a metric SI-prefixed unit for very small torques.

• 1 cN·m = 0.01 N·m
• 1 N·m = 100 cN·m

Why Such a Small Unit

Some torques are genuinely tiny. A spectacle hinge screw, a watch case back or a miniature connector may need a fraction of a newton-meter. Writing 8 cN·m is clearer and safer on a specification than 0.08 N·m, where a missing zero changes the value tenfold.

Because centi is a plain SI prefix, the conversion is exact and involves no measurement standard — just a shift of the decimal point.

Where Centinewton-meters Are Used

• Precision instruments and optics — small retaining screws.
• Electronics assembly — miniature terminal screws and board standoffs.
• Watchmaking and eyewear.
• Torque screwdriver ratings in the sub-newton-meter range.

Converting Centinewton-meter

Pound-inch to Centinewton-meter Conversion Table

Here are some quick reference conversions from Pound-inch (lbf-in) to Centinewton-meter (cNm):