"Laisse(z) tomber" translation or similar French phrases meaning "let it be"?

On a French calendar that I have, "laissez tomber" was translated as "let it be." After researching, however, it seemed like "laissez tomber" was more slang than that, something along the lines of "drop it" or "forget it." Which one is more correct? Are there any other French phrases translating closely to "let it be"? I speak some French, but I'm not familiar with most idioms or slang. Thanks for any help!