when does old faithful erupt

Old Faithful geyser typically erupts every 60 to 90 minutes, with the time between eruptions currently averaging about 74 minutes but ranging from roughly 54 to 118 minutes. Each eruption lasts between 1.5 to 5 minutes, shooting water to heights of 100 to 180 feet. These eruption times can be predicted with about 90% accuracy within a 10-minute margin based on the previous eruption's duration and water discharge. The eruption frequency has changed over time, influenced by events like earthquakes, but it remains very reliable and predictable for visitors wanting to view it.