It's "belongings are". When talking about the things you own or carry with you, this noun only has a plural form and requires a plural form of a verb.

It's "belongings are". When talking about the things you own or carry with you, this noun only has a plural form and requires a plural verb.

Knowing how much your belongings are worth is important.

Knowing how much your belongings is worth is important.

Follow the same rule with other verbs. For example, we say "belongings have" (not "belongings has").

His personal belongings have been stolen.

And remember, plural nouns, like "belongings", take a determiner or pronoun in the plural.

These are my belongings. (not "This")

Your belongings are already packed and on their way. (not "its")

Be also aware that plural nouns cannot be preceded by the article "a".

The belongings are carefully packed.

"Belonging" has a different meaning. This term is an uncountable noun that can be used to describe a feeling of being accepted in a particular place or with a particular group of people. Being uncountable, it takes a verb in the singular.

Belonging is the feeling of identity and inclusion as a member of a certain group.

Follow the same convention of using "are", and not "is", with the plural nouns "contents" and "goods".