The value of PEPE is determined by supply and demand factors, just like all cryptocurrencies. There are several factors that affect it.
First, since PEPE is a meme coin, community activity is of utmost importance. The more buzz there is on social media about the asset, the higher the likelihood of its price rising.
Second, the overall state of the cryptocurrency market is very important. When the market is in a bullish phase, investor interest in major assets increases and their values rise. Conversely, in a bearish phase, buyer interest decreases, and thus the price of PEPE and other crypto assets falls.