The exact number of stars in the universe is difficult to determine with precision due to its vastness and the limitations of our current observational capabilities. However, it is widely believed that there are significantly more than a trillion (10^12) stars in the universe.
Estimates based on observations from various telescopes, including the Hubble Space Telescope, suggest that there could be anywhere between 100 billion to 200 billion galaxies in the observable universe alone. Each of these galaxies can contain millions to trillions of stars.
For instance, the Milky Way, our home galaxy, is estimated to contain roughly 100 billion to 400 billion stars. And considering the vast number of galaxies in the universe, the total number of stars is likely to be several orders of magnitude greater than a trillion.
Moreover, these estimates focus on the observable universe, which is the portion of the universe we can currently observe. The actual universe could extend far beyond what we can see, and there may be regions beyond our observational reach that contain even more stars.
It's worth noting that these numbers are subject to ongoing refinement as new observations and data become available. Nonetheless, the general consensus among astronomers and cosmologists is that the number of stars in the universe is exceptionally vast, far exceeding a trillion.