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Foot-pounds to Inch-pounds Converter
1 ft⋅lb = 12 in⋅lb exactly. Type in either box.
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Exactly twelve
There are twelve inches in a foot, and torque is force times distance, so there are exactly twelve inch-pounds in a foot-pound.
1 ft⋅lb = 12 in⋅lb exactly
Note that this is a straight twelve, unlike area conversions where the length factor gets squared. Torque involves distance to the first power only, so the factor is the plain inch-to-foot ratio.
The two units cover different ends of the same job. Wheel nuts and engine bolts are specified in foot-pounds; small screws, instrument fittings and bicycle parts in inch-pounds.
The foot-pound
One pound-force applied one foot from the pivot. It is the standard torque unit in American automotive and mechanical work, where wheel nuts, cylinder heads and suspension bolts are all specified in it.
One foot-pound is 1.3558 newton-metres, so a torque wrench marked in one scale reads about a third higher on the other.
The inch-pound
A twelfth of a foot-pound, because there are twelve inches to the foot. It is used for small fasteners, where a foot-pound figure would be an awkward fraction: electronics, instruments, aircraft interiors and bicycle components.
The working, step by step
Every line updates with whatever you type above. The point is the method, which is the same for any pair of units in this family.
The same quantity, two different numbers
One physical amount, read off two scales. The tick marks do not line up, and the gap between them is the conversion factor made visible.
How much is that?
A number is easier to judge next to something familiar.
Your turn
Reading a method and being able to use it are different things. Answer within half a per cent and it counts as correct.
Score: 0 of 0
How to use this converter
- Type into either box. The other side updates as you go; there is no button to press.
- Swap the direction with the button between the boxes, carrying your value across.
- Set the decimals if the default is more or less precision than you need.
- Copy the answer with its unit, ready to paste.
- Use the shortcut buttons for the values that come up most often.
- Share the result. The address bar tracks what you type, so the link you copy opens on the same number.
Common uses and tips
Where this comes up
- Tightening fasteners. Torque specifications are the main reason anyone converts these units. Wheel nuts, cylinder heads, bicycle components and aircraft fittings all have figures that must be hit.
- Engine specifications, where European figures are in N⋅m and American ones in lb⋅ft.
- Torque wrenches, which are marked in one scale and used against instructions written in another.
The trap: a newton-metre is not a joule
Torque and energy have identical dimensions — force times distance — but they are not the same quantity. Energy is force applied along a distance; torque is force applied at a distance from a pivot.
By convention torque is always written N⋅m and energy always J, even though the arithmetic is the same. Holding a spanner still against a tight bolt applies torque and does no work at all.
Tips worth knowing
- lb⋅ft and ft⋅lb are the same thing. Both mean pound-force times foot. Different manufacturers write it differently.
- Twelve inch-pounds to the foot-pound, because there are twelve inches in a foot.
- Under-tightening is as bad as over-tightening. A loose wheel nut is dangerous and a stretched bolt is ruined, which is why these figures are worth converting carefully.
- Do not guess from feel. Studies of mechanics show estimates routinely out by 30 % or more.
Values people look up most
Each one opens the converter with the number already in it.
- 0.5 ft⋅lb to in⋅lb
- 1 ft⋅lb to in⋅lb
- 2 ft⋅lb to in⋅lb
- 3 ft⋅lb to in⋅lb
- 5 ft⋅lb to in⋅lb
- 8 ft⋅lb to in⋅lb
- 10 ft⋅lb to in⋅lb
- 15 ft⋅lb to in⋅lb
- 20 ft⋅lb to in⋅lb
- 25 ft⋅lb to in⋅lb
- 30 ft⋅lb to in⋅lb
- 40 ft⋅lb to in⋅lb
- 50 ft⋅lb to in⋅lb
- 75 ft⋅lb to in⋅lb
- 100 ft⋅lb to in⋅lb
- 150 ft⋅lb to in⋅lb
- 200 ft⋅lb to in⋅lb
Quick reference
| Foot-pounds | Inch-pounds |
|---|---|
| 0.5 ft⋅lb | 6 in⋅lb |
| 1 ft⋅lb | 12 in⋅lb |
| 2 ft⋅lb | 24 in⋅lb |
| 5 ft⋅lb | 60 in⋅lb |
| 10 ft⋅lb | 120 in⋅lb |
| 20 ft⋅lb | 240 in⋅lb |
| 50 ft⋅lb | 600 in⋅lb |
| 100 ft⋅lb | 1,200 in⋅lb |
| 150 ft⋅lb | 1,800 in⋅lb |
Questions people ask
How many inch-pounds in a foot-pound?
Exactly 12.
Why is it not 144?
Because torque is force times distance to the first power. The squaring applies to area, not to torque.
What is 10 ft-lb in inch-pounds?
120 in⋅lb.