Per day, 1440 minutes or 86,400 seconds are necessary. A day consists of 24 hours, while an hour is composed of 60 minutes. Therefore, to determine the total number of minutes in a day, you only need to multiply 24 by 60. To get the number of seconds in a day, multiply 1440 by 60. (since 1 minute is comprised of 60 seconds). Each day is composed of 86,400 seconds.