StaymarkWhat the rule says
Visitors who do not need a visa (including UK, US, Canadian and Australian passport holders) may stay in the Schengen area for up to 90 days in any 180-day period. On every day of your stay, count the days you spent in the area during the 180 days up to and including that day. The total must be 90 or less.
Entry and exit days both count
Arriving on a Friday and leaving on the Sunday uses three days, not one or two. Any part of a day in the area counts as a whole day.
Days age out one at a time
Each day you spend drops out of the window exactly 180 days later. That is why the allowance seems to refill gradually instead of resetting on a fixed date. Someone who has used 90 days can only come back as old days fall away.
Which countries count
The Schengen area is Austria, Belgium, Bulgaria, Croatia, Czechia, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Italy, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden and Switzerland.
Ireland and Cyprus are in the EU but not in the Schengen area, so days there do not use your Schengen allowance. Some territories of Schengen countries are outside the area too, such as France's overseas departments, Greenland, the Faroe Islands and Svalbard.
Planning a trip without overstaying
The question that matters is not how many days you have left today, but whether a trip you are planning keeps every 180-day window at or under 90. A long trip months away can breach the rule on a date in the middle of it. Staymark's tracker checks every window as you type the trip, and tells you the latest day you can stay.
Questions
Is it 90 days per country?
No. The 90 days cover the whole Schengen area together.
Does the 90/180 rule reset every January?
No. It is a rolling window with no fixed reset date.
Do days in Ireland or Cyprus count?
No. Neither is in the Schengen area, so days there do not use your Schengen allowance. They have their own entry rules.
Sources
Staymark counts days against published rules. This guide is general information, not legal, tax or immigration advice; rules change, so check the official sources above before you travel.