MEASUREMENT & METHODS

Watt hours per kilogram (Wh/kg): specific energy unit guide

Understand watt hours per kilogram (Wh/kg) for specific energy. Check base-unit equivalents, examples, comparison tables and source conventions.

What is being measured?

Specific energy is energy per mass. Its numerical units do not make it absorbed dose in a biological or radiological application.

Specific energy is not volumetric energy density. Radiation absorbed dose also has J/kg dimensions but a distinct meaning.

Meaning of Wh/kg

Watt hours per kilogram uses the symbol Wh/kg in this library and measures specific energy. Under the stated reference convention, 1 Wh/kg = approximately 3600 J/kg. This equivalence changes how a known value is written. It does not increase measurement accuracy or establish whether a measurement is appropriate to a real application.

Conversion method

Multiply the value by the source factor (3600), then divide by the target factor (1). The factor ratio expresses the same specific energy measurement in the other unit.

Worked example

For a known value of 10 Wh/kg, the reference conversion gives 36000 J/kg. Converting that result back gives approximately 10 Wh/kg. This reverse check helps catch a reversed factor, but matching round-trip arithmetic alone does not independently verify a source definition.

Common reference values

Input (Wh/kg)Reference equivalent (J/kg)
13600
518000
1036000
2590000
50180000
100360000

Compare one Wh/kg with other units

Target unitEquivalent of 1 Wh/kgDefinition guide
Joules per kilogram (J/kg)3600Read definition
Kilojoules per kilogram (kJ/kg)3.6Read definition
Megajoules per kilogram (MJ/kg)0.0036Read definition
Kilowatt hours per kilogram (kWh/kg)0.001Read definition

Precision and common mistakes

  • Keep the source and target quantity consistent. A matching symbol is not enough to establish a compatible definition.
  • Record the original measurement precision. Showing twelve significant digits in a table does not make a rounded input more precise.
  • Check symbol capitalization, prefixes and any regional convention in the source. Use the displayed unit definition rather than a similarly named unit.
  • Factors involving repeating fractions or π use finite numerical precision. Round the final answer to the precision justified by your input.

Use a working converter

Source and verification scope

Examples and tables are computed from the versioned unit definitions used by the linked converters. The source access dates appear below. Computandum is independent of the cited organizations; a citation does not mean that a publisher endorses this page or an actual project.

Sources

Read the calculation and sourcing methodology →