foot-pound to joule Converter
Convert ft-lb to J and back with a live reference table.
1 ft-lb = 1.35582 J\n5 ft-lb = 6.77909 J\n10 ft-lb = 13.5582 J\n25 ft-lb = 33.8954 J\n50 ft-lb = 67.7909 J\n100 ft-lb = 135.582 J
Why this conversion matters
Foot-pounds show up in torque and work examples, while joules are the standard SI energy unit. The widget keeps the direction explicit so you can enter either side of the pair without doing the reciprocal by hand. It is built for quick checks where a calculator, specification sheet, recipe, map, or lab note uses the other unit.
For the default example, 100 ft-lb converts to 135.582 J. Switching the direction shows the inverse relationship, so 135.582 J converts back to 100 ft-lb with the same factor.
Formula and privacy note
The calculation uses 1 ft-lb = 1.35582 J. Forward conversion multiplies by that factor, and reverse conversion divides by it. Results are rounded to six significant figures for readable estimates, so very small scientific units and large planning units stay scannable. Check the unit labels before copying a result, especially when similar abbreviations appear in the same project. The reference table is generated from the same constant, and everything runs locally in your browser.
Frequently Asked Questions
What factor does this converter use?
It uses the standard factor 1 ft-lb = 1.35582 J, then applies the reciprocal for the reverse direction.
Why are results rounded?
The main result is rounded to six significant figures so very large and very small values stay readable while preserving the useful precision for quick checks.
Can I convert both directions?
Yes. Choose ft-lb to J or J to ft-lb from the direction menu and the output updates immediately.
Is this converter private?
Yes. The conversion runs entirely in your browser, and the value you enter is not uploaded or stored.
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