Third-country nationals are able to use the so-called Schengen calculator to make the planning and calculating of their short stay in the EU member states easier.
The Schengen calculator is accessible online. It can be found on the European Commission website:
The calculator is intended for general use by the police, administrative authorities, authorities responsible for issuing visas, and to third-country nationals to calculate or plan short stay on the territory of Member States. Short stay is any stay that is not longer than 90 days in any period of 180 days. Short stay consists of every day of the stay in the last 180-day period.
The user enters in the calculator all dates of the entry and exit stamps from the passport and finds out how long they have stayed on the territory of member states and how much longer they are allowed to stay in them. Information on entry and exit is entered in the format dd/mm/ll (day/month/year), and dates before 22. 4. 2013 cannot be entered due to legal restrictions.
The Schengen calculator is a tool to facilitate the determination of the length of a short stay. The final decision on short stay is the responsibility of authorised authorities.