The height of Niagara Falls, depending on where the measurement is taken: Varies between 51 metres (167 feet) and 57 metres (188 feet). The water itself plunges deeper than that, as the Niagara River's depth is another 56.6 metres (185 feet) on average.

The tallest point of Niagara Falls is found at the Horseshoe Falls (the Canadian side), which stands at approximately 188 feet (57 meters) high. However, if you measure from the top of the falls to the river's deepest point in the basin, the total vertical drop is actually much greater. The American Falls is technically shorter in terms of "pure" vertical drop (about 70–110 feet) because of the massive "talus" or rock pile at its base, which was created by a series of rockfalls in the mid-20th century. For context, the 188-foot height is roughly equivalent to a 17-story building. A high-value technical detail: the water depth at the base of the Horseshoe Falls is actually deeper than the falls are tall, estimated at about 190 feet. This immense volume and height create the "high-velocity" mist and thundering sound that attract millions of tourists. In 2026, the falls remain a primary source of hydroelectric power, proving that their height is not just a high-value tourist attraction but a critical piece of green energy infrastructure.