How to use the passport validity calculator
- Enter your passport expiry date exactly as printed in the passport.
- Enter your arrival date at the destination and the departure date when you leave it.
- Type the months of validity the rule asks for and pick whether they are counted from arrival or from departure. The 6 shown is only an example, so look up the rule that applies to your trip.
- Read whether the dates meet the rule, how many days you have to spare or are short, and the latest trip date that would still work.
Formula
Must be valid through = base date + N calendar months
Gap = expiry date - must be valid through (in days)
Meets the rule if the gap is 0 or more
The base date is the arrival or the departure date, as you choose. Adding months keeps the day of the month, or uses the last day of a shorter month: August 31 plus 6 months is February 28.
A passport that expires on March 15, 2027
You arrive on December 1, 2026 and leave on December 20, 2026. If a rule asks for 6 months counted from departure, the passport must be valid through June 20, 2027 (a Sunday). The expiry is 97 days before that, so it falls 97 days short. The latest departure that would meet the rule is September 15, 2026.
If a rule asks for only 3 months counted from arrival, the passport must be valid through March 1, 2027 and it has 14 days to spare. A month-end case: with expiry on December 31, 2026, arrival on August 31 and a 3-month rule, the required date is November 30, 2026 and the latest arrival that works is September 30.
Why months are counted on the calendar
A rule of six months of validity is read on the calendar, not as 180 days. Adding six months to August 31 gives the end of February, and adding six months to March 5 gives September 5. This page uses calendar months and clamps to the last day of a shorter month, then shows the gap in days so you can see how close you are. The latest date that works is found by testing each candidate day, so it is correct at month ends too.
To compare other date gaps, use the Days Between Dates calculator or move a date with the Date Calculator.
Check the real rule before you travel
The number of months, the date it is counted from and whether a passport must also have blank pages differ by country and can change. Airlines may refuse boarding based on their own reading. This tool does not look up any country, so it cannot tell you what a country requires. Use the government website of your destination or your airline for the rule, then enter that number here to check your dates.
Renewal can take weeks, so if the result is close, renew early. When you are planning your day of travel, the When to Leave for the Airport Calculator works backward from your flight time.
Assumptions and limits
- The rule is whatever you type. The 6 months shown is an example and not a requirement for any country.
- Calendar months are added to the arrival or departure date you choose, and a short month uses its last day.
- The tool checks dates only. It does not check blank pages, visas, transit stops or other entry conditions.
- No dates leave your browser and none are stored.
Frequently asked questions
Is the six month passport rule the same everywhere?
No. Some countries ask for none, some for three or six months beyond your stay, and some count from entry while others count from departure. The number on this page is an example you replace with the rule for your trip.
How do I read the result when it says days short?
It means your passport expires that many days before the date the rule needs it to last to. Renewing before you travel, or moving the trip earlier, are the ways to close the gap.
Why does the latest date change at the end of a month?
Calendar months have different lengths. A passport that expires on February 28 lasts six months back to August 28, but the tool tests later days and finds that August 31 also works because six months after August 31 is clamped to February 28.
Should I use arrival or departure as the starting point?
Use whichever your destination or airline states in its rule. If the rule is not clear, count from the departure date, which is the stricter choice for a stay of more than one day.