Karachi is 9 hours ahead of Philadelphia
Best overlap: 8:00 AM to 9:00 AM in Philadelphia is 5:00 PM to 6:00 PM in Karachi.
Your window to reach both cities is 8:00 AM to 9:00 AM in Philadelphia, which converts to 5:00 PM to 6:00 PM in Karachi. The shared window is only 1 hour — treat 8:00 AM in Philadelphia (5:00 PM in Karachi) as the one fixed point and plan everything else around it. The difference isn't constant year-round: Philadelphia adjusts for daylight saving while Karachi holds steady.