Well, as a matter of fact, this is hard to tell. Because you should know that the purpose of cataract surgery is to keep your eye pressure down, and this does not have relationship with the improvement of your vision. However, if the situation is ok and you pay attention to protect your eyes, you might recover to your previous level of vision, but this will take one or two months. So, it is important to consult the professional doctor.
It depends on individual immune system. Some people need one month, while others need much longer, even one year. But relax, the average recovery time is around 40--60 days. During recovery period, you should take a good care of your eyes. Do not eat too much spicy foods. No smoking and no drinking. Avoiding rubbing your eyes with your hands and staring computer or television in a long time. From now on, you need have a good rest and keep eye clean.
Well, generally speaking, it will take about 3-4 weeks for your vision to be stable. So you should just be patient. As we know that a cataract is a clouding of the normally clear lens of the eye, which can eventually block the central line of sight and impairs vision. So if there are some problems that occur on it, you should take surgery to heal it, such as the cataract surgery. That is to say Cataract surgery is an operation to remove the clouded lens. On the other hand, after you have taken the surgery, there is still something you should pay attention to, because your eyes are very sensitive and fragile at the recovery period. For example, you should not watch TV or computer in the first week, and also should be careful when you have shower. And also, do not take some exercises which can lead to eye strain. Anyway, just be careful about it.