If stored properly, a bottle of red wine can last up to a week after being opened. Without proper storage, it will only last a day or two.
Red wine oxidizes easily, and when it does, it takes on a vinegar taste. Therefore, in order to store an opened bottle of red wine longer, the contents must have minimal contact with oxygen. Consumers can store the wine on its side in a wine cooler or another cool, dark place. This will keep the cork from drying out, shrinking and allowing oxygen into the bottle. Each time someone uses the wine, they need to put back the cork immediately to ensure the wine lasts as long as possible.