What is the time of iftar? Is it the time of maghrib at night when it is dark?

Most scholars say when the redness in the eastern horizon (the side opposite to sunset) disappears. This happens usually about 15 minutes after the sun sets. So when it gets a little darker. And some scholars state that as soon as the sun sets then one can break their fast. It’s best to wait about 15 minutes after sunset then break one’s fast.