Knowing your body's needs for fluids will help determine how much water you really need per day. It depends on your activity level, your health in general, etc.
For Dietary recommendations, men need to drink about 3 liters of water per day, women 2.2 liters. A good indication on whether you need more or not is if you're passing 1-2 liters of colorless or slightly yellow urine a day, your water intake is probably adequate. Depending on how intense your exercise routine is depends on how much you need before & after, too. Generally, if you're running or exercising for an hour or more, you need an extra 13-26 ounces of water! Our kidneys are equipped to efficiently process fifteen liters of water per day, if that tells you anything
Your body will let you know whether your water intake is too much or not enough
I hope this helps!!