General calmness:
* Kalmado/a (masculine/feminine) - This is the most common and direct translation of "calm".
* Tahimik - This means "quiet" but can also imply calmness.
Specific situations:
* Mapayapa - This means "peaceful" and implies a sense of tranquility.
* Nagpapahinga - This means "resting" and can be used to describe someone who is calm and relaxed.
* Walang kinakabahan - This literally translates to "not nervous" and can be used to describe someone who is calm and collected.
To describe a place or environment:
* Mapayapang lugar - This means "peaceful place".
* Tahimik na kapaligiran - This means "quiet environment".
The best translation will depend on the specific context.