# Watt second conversions

The watt second conversion selector on this page selects the energy measurement unit to convert to starting from watt seconds (Ws). To make a conversion starting from a unit of energy other than watt second, simply click on the "Reset" button.

## About watt second

The **watt second**, or **watt-second**, is a derived unit of energy equal to one joule (1 Ws = 1 J), the SI derived unit of energy.

The watt second (Ws) is also equal to 0.001 kilojoules (kJ), or 2.7777778 × 10^{-4} watt hours (Wh), or 2.7777778 × 10^{-7} kilowatt hours (kWh), or 2.7777778 × 10^{-10} megawatt hours (MWh) or 2.7777778 × 10^{-13} gigawatt hours (GWh).

The watt second is the energy required to produce one watt of power for one second. The watt (W) is a derived unit of power in the SI while the second (s) is an SI unit of time.

Symbol: Ws

Plural: watt seconds

Also known as: watt-second (plural: watt-seconds)