Convert inch-pounds to foot-pounds and back. Shows N·m, kgf·cm, oz·in equivalents plus common torque specs for automotive, bicycle, and mechanical applications.
This converter handles the straight imperial torque change from inch-pounds to foot-pounds. It is useful when a manual or spec sheet uses one imperial unit and your wrench, chart, or habit uses the other.
The relationship is fixed at 12 inch-pounds per foot-pound, so the conversion itself is simple. The rest of the page shows the related torque units, including newton-meters, kilogram-force centimeters, and ounce-inches, so you can compare the same spec in the range that makes most sense for the job.
Use it for fastener work on cars, bikes, small engines, and similar maintenance tasks where the only real question is which torque scale the documentation used. It is also handy when a service manual lists smaller cover bolts in inch-pounds but the rest of the job is discussed in foot-pounds, or when you want to sanity-check a torque wrench setting before tightening a part that is easy to strip or crack.
A factor-of-12 unit mistake is easy to make when the spec and the wrench are both imperial. This page keeps inch-pounds and foot-pounds aligned, shows the same torque in several secondary units, and gives enough context to check that the setting on the wrench actually matches the fastener spec you are trying to follow.
Inch-Pounds to Foot-Pounds: ft·lb = in·lb / 12 Foot-Pounds to Inch-Pounds: in·lb = ft·lb × 12 Inch-Pounds to Newton-Meters: N·m = in·lb × 0.112985 Inch-Pounds to kgf·cm: kgf·cm = in·lb × 1.15212 Inch-Pounds to Ounce-Inches: oz·in = in·lb × 16
Result: 10 ft·lb
120 inch-pounds divided by 12 equals exactly 10 foot-pounds. This is also 13.558 N·m. A torque of 10 ft·lb is common for small engine exhaust manifold bolts.
Torque measures a twisting force and equals force multiplied by the lever arm distance. In imperial units, a foot-pound is one pound-force applied at the end of a one-foot lever; an inch-pound uses a one-inch lever. The factor of 12 between them comes directly from the 12 inches in a foot. Both are commonly used in US automotive, aerospace, and manufacturing settings.
Torque wrenches come in different ranges: micro (1-50 in·lb), small (20-250 in·lb), medium (10-150 ft·lb), and large (50-600 ft·lb). Using a wrench at the very bottom of its range reduces accuracy, so match the wrench to your specific torque requirement. For precision work, a digital torque wrench offers +/-1% accuracy versus +/-3-4% for click-type wrenches.
The most dangerous conversion error is confusing in·lb with ft·lb - torquing to 50 ft·lb when the spec is 50 in·lb means applying 12× the intended force. Other pitfalls include torquing dirty or lubricated threads without adjusting the spec, reusing torque-to-yield bolts, and not following a star or cross tightening pattern on multi-bolt flanges.
Exactly 12 inch-pounds equal 1 foot-pound. To convert ft·lb to in·lb, multiply by 12. To go the other way, divide by 12.
Use inch-pounds for small fasteners that require low torque - typically under about 200 in·lb (about 17 ft·lb). Examples include electronics screws, bicycle bolts, and small-engine components.
Not accurately. A foot-pound wrench typically starts at 10 ft·lb (120 in·lb), and resolution at the low end is poor. Use a dedicated inch-pound torque wrench for specs under 120 in·lb.
Over-torquing can strip threads, stretch the bolt past its elastic limit, crack cast components, or crush gaskets. Any of these failures can compromise clamp load and cause joint failure in service.
In engineering notation, it is written as in·lb (with a center dot) or in-lb (hyphenated). "Inch-pound" is standard in prose. All forms refer to the same unit.
Multiply inch-pounds by 0.112985. For example, 120 in·lb × 0.112985 = 13.558 N·m. You can also convert to ft·lb first (÷12) then to N·m (×1.35582).