Controlled unit worksheet
Torque Unit Conversion
Convert a signed moment-of-force or torque value through N·m using documented conversion factors. This page converts units only; it does not select a tightening torque or assess equipment.
Input
Conversion record
| Unit | Converted value |
|---|---|
| N·m | — |
| N·mm | — |
| mN·m | — |
| dN·m | — |
| kgf·m | — |
| lbf·ft | — |
| lbf·in | — |
| ozf·in | — |
Method and factors
Canonical calculation
Each input is first converted to N·m and then divided by the target-unit factor:
xto = M[N·m] / cto
The same signed physical quantity is represented in every row. Conversion does not change direction, uncertainty or meaning.
Factors used
1 mN·m = 0.001 N·m
1 dN·m = 0.1 N·m
1 kgf·m = 9.80665 N·m
1 lbf·ft = 1.3558179483314004 N·m
1 lbf·in = 0.1129848290276167 N·m
1 ozf·in = 0.007061551814226043 N·m
The lbf-based factors are derived from the NIST exact lbf factor at standard gravity and the exact international foot/inch definitions. This preserves exactly 12 in = 1 ft and 16 ozf = 1 lbf. Displayed digits do not create measurement accuracy.
Quantity and notation
Torque is not energy
BIPM identifies torque as the cross product of position and force. Its SI unit is N·m. Torque and energy share dimensions, but the joule is not used for torque; the quantity name and context matter.
Force units, not mass units
kgf, lbf and ozf are force units. They must not be confused with kg, lb or oz mass.
SI prefixes
dN·m means decinewton metre and equals 0.1 N·m. mN·m means millinewton metre. N·mm and mN·m are numerically equal for the same torque, but their written unit expressions differ.
Signed values
A minus sign is retained in every output. It has meaning only after the user defines an axis and positive direction; the converter does not decide clockwise/counter-clockwise or input/output direction.
Sources and normative status
| Source | Verified use | Boundary |
|---|---|---|
| BIPM SI Brochure, 9th edition, version 4.01 (2026) | Torque unit N·m; torque/energy distinction; SI prefix values. | Official SI publication. |
| NIST SP 811, Appendix B.8 and footnote 23 | kgf·m and moment-of-force factors; exact lbf conversion at standard gravity; foot/inch relations. | Official conversion table and definition note. Decimal calculation is shown transparently. |
| ISO 80000-4:2019 + Amd 1:2025 | Official public lifecycle and mechanics quantities/units scope. | Published and marked to be revised; exact clauses require a licensed controlled copy. This converter makes no ISO-conformity claim. |
Check example
Using the derived factor, 10 lbf·ft × 1.3558179483314004 = 13.558179483314004 N·m. The same quantity is exactly 120 lbf·in before display rounding because 1 ft = 12 in.
Nikolai Shelkovenko
Nikolai Shelkovenko is a vibration analysis engineer and the founder and CEO of Vibromera. For more than 15 years he has balanced rotating equipment in the field rather than on a test bench: mulchers, industrial fans, crushers, centrifuges, shafts and spindles. That work is what the Balanset instruments grew out of — they were designed as a tool a specialist can carry to the machine and use alone, on site, not as laboratory equipment. Vibromera was founded in 2017 and has been based in Porto, Portugal, since 2023. Development, assembly and support of the Balanset line all happen here. The flagship instrument is the Balanset-1A, a portable analyser for single- and two-plane balancing and for vibration diagnostics. Nikolai is personally involved in customer support, in working through difficult balancing cases and in the development of the software. He works with customers worldwide, in any language.
