How many dollars is a token?

Good day, fellow enthusiasts in the crypto world. I've been observing the markets lately, and a question has been lingering in my mind. As we all know, the value of cryptocurrencies and tokens can fluctuate quite significantly. But I'm curious to know, in a general sense, how many dollars does a token represent? Is there a fixed exchange rate? Or does it vary based on supply and demand? Additionally, I'm interested to understand if there's a standard method to determine the dollar value of a token, or if it's more of a subjective assessment? I'd appreciate any insights or explanations you could provide on this matter. Thank you for your time and consideration.