* Light pollution: In heavily light-polluted areas, only a few dozen stars might be visible.
* Observing conditions: Clear, dark skies with minimal atmospheric interference allow for many more stars to be seen.
* Observer's vision: Some people have better eyesight than others.
* Definition of "visible": Some stars are so faint that they're barely perceptible, while others are quite bright.
However, under ideal conditions, with a perfectly dark sky and good eyesight, you can see roughly 2,000 to 2,500 stars.
Note: This is just a rough estimate. The number can vary significantly depending on the factors mentioned above.