How Sunrise & sunset times works
This calculator gives you the sunrise, sunset, solar noon and day length for a latitude, a longitude and a date. Enter the coordinates yourself, or tap "use my location" to fill them from your device. Pick the time zone from the list and the wall-clock times follow it, with daylight saving handled for the date you chose rather than a fixed numeric offset you would have to adjust twice a year.
The times come from the NOAA solar position algorithm. That model assumes a flat horizon at sea level and a standard amount of atmospheric refraction, so it does not know about the hill in front of you, your altitude, or the haze on a given morning. In open, flat terrain the result is usually within a minute or two of what you observe; behind mountains or on a hazy day the gap can grow to several minutes. Treat it as a solid planning figure, not a stopwatch reading.