The galaxies we can see are just the tip of the galactic iceberg. For every galaxy we can see, there are another 9, smaller fainter galaxies that we can’t see. Of course, we’re just a few years away from being able to see these dimmer galaxies.
https://www.universetoday.com/30305/how-many-galaxies-in-the-universe/
There may actually be 10 times more galaxies in the universe than we previously thought. Before today, the best estimate of the number of galaxies existed in the universe came from a 1995 observation by Hubble, shortly after it was repaired in orbit. That’s when NASA used the space telescope to observe a patch of sky continuously for 10 days.
https://www.extremetech.com/extreme/237725-there-may-be-10-times-more-galaxies-in-the-universe-than-we-thought
In the past, astronomers divided that total mass by the number of galaxies they could see in the original Hubble data and determined there were about 200 billion galaxies. Now, astronomers used a new technique to estimate the galaxies and it’s pretty cool.
https://www.universetoday.com/30305/how-many-galaxies-in-the-universe/
How do we know how many galaxies are in our universe? According to the best estimates of astronomers there are at least one hundred billion galaxies in the observable universe. They’ve counted the galaxies in a particular region, and multiplied this up to estimate the number for the whole universe.
http://www.physics.org/facts/sand-galaxies.asp
The result gave us the information that a very large number of galaxies exist in a minuscule region of the sky: around 10,000 in the tiny volume surveyed by the Hubble Ultra Deep Field image, below. 1  Image credit: NASA, ESA, S. Beckwith (STScI) and the HUDF Team.
http://blogs.discovermagazine.com/crux/2012/10/10/how-many-galaxies-are-there-in-the-universe-the-redder-we-look-the-more-we-see/
The estimated number of galaxies in the observable universe is around 100-200 billion, with exponentially many more estimated in the non-observable universe. Ten times 200 billion though would be 2 trillion.
https://www.extremetech.com/extreme/237725-there-may-be-10-times-more-galaxies-in-the-universe-than-we-thought
In fact, with 10 times the number of galaxies, you could restate the paradox and say that in every direction, you should be looking at a galaxy, but that’s not what you see. A partial map of the distribution of galaxies in the SDSS, going out to a distance of 7 billion light years.
https://www.universetoday.com/30305/how-many-galaxies-in-the-universe/
You see, there might be at least 100 billion galaxies, based on what we’ve observed, but there might be more. Galaxies that are too dim to observe with “only” 11 days of Hubble data. Galaxies that are redshifted too far for even Hubble’s farthest infrared filter to pick up.
http://blogs.discovermagazine.com/crux/2012/10/10/how-many-galaxies-are-there-in-the-universe-the-redder-we-look-the-more-we-see/
But there are maybe 75% more galaxies-per-patch-of-sky in the XDF! Applying the XDF results to the entire sky, we find that there are more like 176 billion galaxies in the entire Universe, a huge increase from our previous estimate from the HUDF.
http://blogs.discovermagazine.com/crux/2012/10/10/how-many-galaxies-are-there-in-the-universe-the-redder-we-look-the-more-we-see/
500 Billion --A Universe of Galaxies: Some Older than Milky Way. June 10, 2013. he Hubble Space Telescope site estimates there are hundreds of billions of galaxies in the universe. A recent German super-computer simulation estimates that the number may be as high as 500 billion, with many older than the Milky Way.
http://www.dailygalaxy.com/my_weblog/2013/06/500-billion-a-universe-of-galaxies-some-older-than-milky-way.html
how many galaxies exist?
100 to 200 billion galaxies exist.