There are a few ways to tell if an avocado is bad. First, check the color of the skin. If it’s brown or black, the avocado is probably spoiled. Another way to tell is by feeling the flesh of the fruit. If it’s mushy or has brown spots, it’s most likely bad. Finally, you can try smelling the avocado. If it has a sour or unpleasant odor, it’s probably not good to eat. If you’re still not sure, it’s best to err on the side of caution and throw it out. Thanks for reading!