There's no right or wrong answer to this question, as it depends on what you want to do on your Las Vegas holiday. If you're looking to see all the sights and enjoy all the nightlife, then you'll need at least a week. However, if you're just looking to relax by the pool, then a few days will suffice.
It's important to note that Las Vegas is a very spread out city, so you'll need to factor in travel time when planning your itinerary. If you're staying on the Las Vegas Strip, then most of the city's attractions will be within walking distance. However, if you're staying off the strip, then you'll need to take public transport or a taxi to get around.
No matter how long you stay in Las Vegas, you're sure to have an incredible time! Las Vegas is a truly unique city that has something for everyone.