3 liters of water is a common volume that you can visualize as being about the size of a 1-gallon jug. This amount of water weighs 6.61 lb (3 kg) and fills a glass 6.03 in (15.3 cm) wide.

In kitchen measures
12.7 cups
609 tsp · 203 tbsp · 12.7 cups
about the size of a 1-gallon jug
Water typically ranges 1–1 g/mL depending on how it's packed. A firmly packed scoop weighs more.