How much time a connection really needs

Airlines publish minimum connection times for each airport, so a sold itinerary should be technically possible. Possible and comfortable are different things.

Add time when you cross a border. Arriving in the United States from abroad usually means clearing immigration, collecting checked bags and re-checking them, even on a connecting flight.

Consider the airport as well. Changing terminals can take longer than the walk suggests, particularly where it involves a train or bus.

Check how the trip was ticketed. On a single ticket, the airline normally rebooks you if a late first flight causes a missed connection. On separate tickets, that protection often does not apply.