Formal:
* De nada: This is the most common and formal way to say "you're welcome".
* Não há de quê: This is another formal option, meaning "it's nothing" or "don't mention it".
Informal:
* De nada: This is also used informally.
* Por nada: This is another informal option, meaning "for nothing".
* De boas: This is a very informal and slang expression, meaning "no worries".
Other options:
* Disponha: This is a more polite and slightly formal way of saying "you're welcome", meaning "feel free".
* É com prazer: This means "it's a pleasure" and is used when you were happy to help.
The best way to choose the right phrase depends on the situation and your relationship with the person you are speaking to.
Example:
* Formal: "Obrigada pela sua ajuda!" "De nada!"
* Informal: "Valeu pela dica!" "Por nada!"
Remember that Portuguese is spoken in several countries, and there may be regional variations in the language.