Most visa tools ask for one nationality. If you hold two or three passports, enter them all: for every country we show the easiest entry any of your passports gets, which passport to travel on, and where your second passport opens a door the first one doesn't.
The working rule: use your own country's passport when entering that country, and whichever passport gives you the easiest entry everywhere else. Some countries require their citizens to use their own passport — the United States, Australia and, for flights, Canada (Canadian-American dual citizens excepted). Read which passport to use as a dual national for the details and sources.
A second passport adds far less than its ranking suggests when your first is already strong: a German passport gains two destinations from an Irish one and fourteen from a Beninese one. We worked out which second passport adds the most for common nationalities.
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