Comparison Rotex RKT10-B 1500 W 1.5 L stainless steel vs Scarlett SC-EK21S40 1500 W 1.6 L stainless steel

The nominal capacity of a kettle refers to the maximum amount of water that can be safely poured into it, and it is typically indicated by the water level indicator. In the case of brewing sets (see "Type"), the nominal capacity refers to the main kettle, while the capacity of the teapot is listed separately (see below).

The capacity of the electric kettle directly affects the amount of water that can be heated at once. A larger capacity allows for heating more water, but this also means the kettle will be larger and heavier. Additionally, heating a larger volume of water requires either more power or a longer time. Therefore, it is important to consider one's actual needs when choosing a kettle based on its capacity. For example, mini-kettles for travelling (or for one person) have a volume of up to 1 liter. For home use in a family of 2 – 3 people, a 1,5 – 2 liter model is enough. Devices for 2 – 3 liters are already well suited for a small office or a similar situation. The most spacious electric kettles are designed to hold 10 liters or more, and are typically used in public places such as canteens and cafes for dispensing hot water.