What are the opposite words for useless?

When we want to express the opposite of "useless," we can use the word "useful." "Useful" means effective, helpful, and valuable. Another term that can be used as an antonym for "useless" is "beneficial." This word implies that something provides a benefit or improves a situation. In contrast, "useless" suggests that something is not needed, doesn't work, or is just a waste of time. Another antonym for "useless" could be "productive," as it is an adjective that describes an activity or thing that is capable of producing results. Alternatively, "functional" is another antonym that means that something has a practical purpose and is working or operating as intended.