lbf·ft to N·m: 1 lbf·ft = 1.355817948 N·m

The formula

N·m = lbf·ft × 1.355817948

Where the factor comes from — each unit by its definition, then its size in SI:

1 lbf·ft = lbf × ft = 1.35581794833 N·m
1 N·m is the SI unit of torque.

Dividing the two SI sizes gives the factor: 1.35581794833 (rounded for display; the underlying ratio is fixed by the definitions). The reverse factor is 0.737562149277.

Torque is force times lever arm, in newton-metres. Workshop manuals mix N·m, lbf·ft and lbf·in; a torque wrench set in the wrong unit over- or under-tightens by a large factor.

Worked examples

A car wheel nut: 81.1318 lbf·ft = 110 N·m — 81.1318 × 1.355817948 = 110
A bolt spec in a US manual: 30 lbf·ft = 40.6745 N·m — 30 × 1.355817948 = 40.6745
A bicycle stem bolt: 7.37562 lbf·ft = 10 N·m — 7.37562 × 1.355817948 = 10

Frequently asked questions

How many newton-metres is 1 lbf·ft?

1 lbf·ft = 1.35581794833 N·m.

How do I convert newton-metres back to pound-feet?

Divide by 1.35581794833 — or multiply by 0.737562149277: 1 N·m = 0.737562149277 lbf·ft.

lbf·ft to N·m conversion table

Pound-feet (lbf·ft)	Newton-metres (N·m)
1	1.3558179
2	2.7116359
3	4.0674538
4	5.4232718
5	6.7790897
6	8.1349077
7	9.4907256
8	10.846544
9	12.202362
10	13.558179
15	20.337269
20	27.116359
25	33.895449
30	40.674538
40	54.232718
50	67.790897
60	81.349077
70	94.907256
75	101.68635
80	108.46544
90	122.02362
100	135.58179
150	203.37269
200	271.16359
250	338.95449
500	677.90897
1,000	1,355.8179

Definitions: NIST Special Publication 811 (2008), Guide for the Use of the International System of Units, Appendix B — https://www.nist.gov/pml/special-publication-811 · BIPM, The International System of Units (SI Brochure), 9th edition (2019), Tables 2, 4 and 8 — https://www.bipm.org/en/publications/si-brochure. Machine value of the factor: 1.35581794833.