Sources and method
How dates are counted
Dates are calendar days without a time: time zones and clock changes never change a result. Days are counted from the day after the start; with the option "count the start day", the start is day 1.
Months go date to date and end on the last day of a shorter month. Working days are Monday to Friday minus the national public holidays of the chosen country, computed from the rules set by law for any year from 1900 to 2100.
Situations
A 90-day stay counts the arrival day as day 1. In the Schengen area, the rule is 90 days in any 180-day period: use the official EU calculator when you have made earlier stays.
There is no general right of withdrawal for online purchases in the United States, so no such situation is offered in English.
Corrections
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