US Citizenship (N-400) Calculator

Enter your green card date and your trips outside the United States. See your earliest filing date, count your days of physical presence, and check for trips that could break continuous residence.

Rules last checked against official sources: 29 September 2026

The "Resident Since" date on your green card.
Your route
Defaults to today.
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The time rules for naturalization

To file Form N-400 you must meet three separate time-based requirements. This calculator checks the first three below. The fourth is a reminder you'll need to confirm yourself.

Requirement5-year route3-year route (spouse of US citizen)
Time as a permanent resident5 years (you can file 90 days early)3 years (you can file 90 days early)
Physical presence in the USAt least 913 days (30 months)At least 548 days (18 months)
Continuous residenceNo trip of 1 year or more. Trips over 6 months are presumed to break it.
Residence in your state or USCIS district3 months before filing

How days are counted

USCIS counts the day you leave and the day you return as days of physical presence in the United States. Only the full days in between count as days outside the country. For example, leaving on 1 March and returning on 11 March is 9 days outside the US, not 11. This calculator uses the same method.

Physical presence is counted over the 5 years (or 3 years) immediately before your filing date. If you file early, only the time since you became a permanent resident is counted.

Filing 90 days early

You can file up to 90 days before your 5-year or 3-year permanent resident anniversary. You must still meet every other requirement on the day you file. If you file even one day too early, USCIS will deny the application and keep the fee. That's why the calculator shows the exact earliest date.

Long trips and continuous residence

Form N-400 asks you to list every trip outside the US that lasted more than 24 hours during the last 5 years. Use Export CSV or Print / save PDF above to prepare that list, and check it against your official I-94 travel history from CBP.

Frequently asked questions

How many days do I need to be in the US to apply for citizenship?
At least 913 days in the 5 years before you file (5-year route), or 548 days in the 3 years before you file if you are married to and living with a US citizen.
Do departure and return days count as days outside the US?
No. USCIS counts both the departure day and the return day as days physically present in the United States.
When is the earliest I can file Form N-400?
90 days before your 5-year (or 3-year) permanent resident anniversary, as long as you meet every other requirement on that date.
Does a 7-month trip disqualify me?
Not automatically. A trip longer than 6 months but shorter than 1 year creates a presumption that continuous residence was broken. You can rebut it with evidence of continuing ties to the US.
Where can I find my exact travel dates?
You can request your travel history (I-94) online from US Customs and Border Protection, and compare it with your passport stamps.

Official sources