Universal Studios Hollywood needs at least 1 full day to inspect. If you have a regular ticket, then one day you may not be enough. Everything will depend on the season, when you go on a trip. If it is a high season, then there will definitely be queues for rides. I would recommend buying tickets for Front of the Line or VIP Tickets, which will allow you to visit all rides without waiting.

It is better to buy tickets in advance, so as not to waste time on their purchase through the cashier, but immediately go and enjoy the incredible attractions.