Convert Ounce-inches to Pound-inches

Formula

lbf·in = ozf·in ÷ 16

Derivation from SI units:

• 1 ozf·in = 1/16 lbf·in = 0.00706155181 N·m
• 1 lbf·in = 4.4482216152605 N × 0.0254 m = 0.1129848290276 N·m
• 1 ozf·in = 0.007061551814226 N·m ÷ 0.1129848290276 N·m per lbf·in = 0.0625 lbf·in

Both units are defined exactly, so the factor is exact. Ounce-inch definition: ounce-inch; Pound-inch definition: pound-inch.

Worked examples

1. A reading of 10 ozf·in converts to 0.625 lbf·in.
   10 ozf·in × 0.0625 = 0.625 lbf·in
2. A value of 100 ozf·in is 6.25 lbf·in.
   100 ozf·in × 0.0625 = 6.25 lbf·in

Where it's used

Ounce-inches are used for stepper and servo motor holding torque, while pound-inches appear in small fastener and electrical-terminal torques. Both measure torque (moment of force), so the conversion is a fixed factor.

Ounce-inch to other torque units

Frequently asked questions

Sources

• Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "ounce (avoirdupois)-force inch".
• Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "pound-force inch (lbf·in)".

Last reviewed: 2026-10-15. Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.