The card is there for 1 to 7 days. For children 4 to 11 years there is the very economical Children's Day card.
The GVB day or multi-day tickets allows you to travel at the hours of your own convenience without any limitation throughout Amsterdam, day and night, on the bus, tram, and metro. The day card is valid for 24 hours after you first check in.
Note: these tickets are only valid in GVB metros, trams, and buses. Thus, these are not valid in the regional buses of Connexxion and EBS or on the train.