How tall is Niagara Falls?
Niagara Falls is actually three waterfalls, and they have different heights. The tallest is the American Falls, which drops about 180 feet (55 meters) straight down. The Bridal Veil Falls, next to it, is similar at roughly 180 feet. The biggest one, the Canadian Horseshoe Falls, is about 188 feet (57 meters) tall, but it's also wider and more powerful. Don't let the numbers fool you—the real kicker is the water volume, not just the height. For comparison, Angel Falls in Venezuela is 15 times taller, but Niagara moves millions of gallons per minute.
If you're standing on the American side, you'll get a face-on view of the American Falls. On the Canadian side, you see the full sweep of the Horseshoe Falls. The actual drop height from the top of the falls to the bottom of the gorge is around 170-180 feet for all three, but the water depth at the base (the plunge pool) makes the total cliff height less dramatic. The official "height" you'll see on signs is usually from the top of the falls to the top of the rock pile at the base, not the river surface.
Bottom line: it's not a skyscraper, but the sheer force and mist make it feel huge. If you want a number to brag about, say "about 180 feet" and you're covered. No need to overthink it—just go see it, especially from the Canadian side for the full effect.