How do you say not much in Spanish?

Literal translations rarely have the same meaning in both languages, and most translations rely on the greater context of the sentence and/or scenario.

For example, the literal translation of "not much" is 'no mucho." But depending on your context, you might also use "No hay mucho (there is not much of a particular physical object)," "poco/poquito (little/infrequent)," or any number of minimizing Words.

If you mean it as in a response to "What's up?" ("¿Qué tal?" or "¿Qué pasa?") the answer is usually "nada", which means "nothing" in Spanish.