When do the forex sessions actually overlap on my own clock?

How this is calculated

• Forex sessions are fixed to UTC by convention rather than a home exchange's local clock: Sydney 22:00–07:00 UTC, Tokyo 00:00–09:00 UTC, London 08:00–17:00 UTC, New York 13:00–22:00 UTC. Each overlap window is the intersection of two of those fixed UTC ranges, converted straight into your selected time zone.
• The three overlaps: Sydney/Tokyo runs 00:00–07:00 UTC (7 hours), Tokyo/London runs 08:00–09:00 UTC (1 hour), London/New York runs 13:00–17:00 UTC (4 hours). London/New York is the longest overlap and, by trading-desk convention, typically carries the heaviest volume and tightest spreads of the three, since it's the only window where two of the three largest forex trading centers are both open.
• "Next day" next to a time means that window's close (or open) falls after midnight relative to its own open, on your local calendar.
• These are the fixed weekly session windows, not live open/closed status, and this does not adjust for market holidays. Confirm against your broker's own trading calendar before you plan around any of these times.