If you're talking about worth or importance:
* Worthlessness: This is the most direct opposite, emphasizing a lack of value.
* Uselessness: This highlights a lack of practical value or function.
* Futility: This suggests a lack of purpose or meaning.
* Insignificance: This emphasizes a lack of importance or impact.
If you're talking about a specific item or concept:
* Disvalue: This specifically indicates a negative value, often in contrast to something else.
* Devaluation: This refers to a decrease in value, often due to economic factors.
* Negativity: This can be used broadly to describe something that lacks positive value.
If you're talking about principles or beliefs:
* Anti-value: This refers to a principle that directly opposes a particular value.
Ultimately, the best opposite for "value" depends on the specific context in which you're using it.