Compatibility summary
Your Japan plug may fit in Antigua and Barbuda outlets, as both use at least one common plug type. Voltage differs by more than 20% — a voltage converter may be needed for some appliances.
Plug comparison
Japan plug types: A B
Antigua and Barbuda plug types: A B
Both countries share at least one plug type (A B and A B), so some plugs may work without an adapter. Check your appliance.
Voltage comparison
Japan: 100V, 50Hz
Antigua and Barbuda: 230V, 60Hz
Voltage converter recommended (Japan 100V vs Antigua and Barbuda 230V).