Rio de Janeiro is 8 hours behind Islamabad
Best overlap: 4:00 PM to 6:00 PM in Islamabad is 8:00 AM to 10:00 AM in Rio de Janeiro.
Aim for 4:00 PM to 6:00 PM Islamabad time — that's 8:00 AM to 10:00 AM over in Rio de Janeiro. Since Rio de Janeiro is 8 hours behind Islamabad, the overlap is narrow (about 2 hours); a single, well-protected slot beats hunting for time each week.