TL;DR — Key Takeaways
- →330 days in a 12-month period is the physical presence test, not the tax result.
- →Bona fide residence is a different qualifying test for the same exclusion.
- →Form 2555 (exclusion) and Form 1116 (foreign tax credit) can produce different US tax on the same salary.
- →High foreign tax often favors the credit; a low-tax host often favors the exclusion. Model both.
Short answer
A 330-day calculator tells you whether you might qualify for the foreign earned income exclusion under the physical presence test. It does not tell you whether the exclusion or the foreign tax credit leaves you with less US tax.
What the day counter omits
- Bracket-level US tax with and without the exclusion
- Foreign tax you already paid, and whether the credit offsets more than the exclusion saves
- Housing exclusion arithmetic
- The bona fide residence test, which is not a 330-day count
Use the free FEIE day calculator for presence days. Use the Premium FEIE vs FTC optimizer when you need both elections on one salary before you talk to a preparer. The optimizer is a planning model, not a filed Form 2555 or Form 1116.
Educational planning only — not tax advice.