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Sources and Accuracy
Energy conversions use joule as the reference unit, including electrical, thermal, nutrition, and mechanical energy units.
Displayed results are rounded for readability. The calculator keeps enough precision for everyday use and switches to scientific notation for very large or very small values. Last reviewed: 2026-05-21.
About These Units
foot-pound [ft-lb]
Definition
The foot-pound (ft-lb) is a energy unit used to express measurements in this converter.
History
This unit is included because it appears in practical measurement systems, technical references, product specifications, or everyday conversion needs.
Current use
Use foot-pound when comparing energy values, checking specifications, converting between systems, or preparing quick estimates.
kilojoule [kJ]
Definition
The kilojoule is an energy unit equal to 1000 joules.
History
Kilojoules are a metric multiple of joules and became common where joules are too small.
Current use
Kilojoules are used for food energy labels, thermodynamics, exercise energy, and engineering calculations.