How to Use the Time Zone Overlap Calculator
Remote work and global collaboration make scheduling across time zones a daily challenge. This calculator helps you instantly find the hours when both teams are simultaneously online. Select two city time zones, set each team's available working hours, and the tool shows the overlapping window in both local times.
The calculator converts each city's work schedule to UTC, finds the intersection, then displays the result in each city's local time. For example, New York (UTC-5) and London (UTC+0) have a 5-hour gap — with 9–5 hours for both, they share roughly 4 hours of overlap (9 AM–1 PM ET / 2 PM–6 PM GMT). When there's no overlap, the result shows "no overlap," signaling that one team may need to adjust their hours.
Note: This tool uses fixed UTC offsets and does not account for daylight saving time (DST). During DST, actual overlap may differ by one hour for affected regions. Always verify before scheduling critical meetings.
Frequently Asked Questions
No — this tool uses fixed UTC offsets. During DST, the actual overlap for US and European cities may differ by one hour. Verify current offsets before scheduling important meetings.
With standard 9 AM–6 PM hours, New York (EST) and London share about 4 hours of overlap — 9 AM–1 PM ET / 2 PM–6 PM GMT.