Used with as to say that one action is just as reasonable, hard, or pointless as another.; to do sth because it seems best in the situation that you are in, although you may not really want to do it
Editorial67% of films
Used with as to say that one action is just as reasonable, hard, or pointless as another.
You may as well do anything most hard as seek to soften that
You may as well do it with your mouths.
Oxford33% of films
to do sth because it seems best in the situation that you are in, although you may not really want to do it
And then I thought I may as well do the rest.
Definitions from the Oxford Advanced Learner's Dictionary, 9th edition