Direct answer
Forex has no single official “session length” like a stock exchange trading day. In practice, the market trades continuously from the week’s open to its close (roughly 24 hours per day on weekdays), while liquidity and participation are often discussed in terms of regional session windows.
A common way to describe “how long sessions last” is by these approximate session labels:
- Asia/Tokyo: roughly the overnight-to-morning hours
- Sydney: often early Asia time (often discussed alongside the Asia window)
- London/Europe: late morning into afternoon Europe/UK time
- New York: late afternoon into evening US time
Because these windows overlap, the “session” a trader refers to may last several hours, but the overall market remains open for far longer than any single window.
How “session length” works in forex
A forex trading session window is a convention for when a particular region’s banks and liquidity providers are most active. It is not a rule that trading closes outside those hours. Instead, outside peak regional hours, trading can be lighter.
Key implications for timing:
- Overlaps matter: London and New York frequently overlap, which often corresponds to periods of higher activity.
- Instrument choice matters: some currency pairs may have more consistent liquidity than others across the week.
- Weekends are a hard boundary: the market is not continuously open across weekends, so “session length” should be interpreted within the weekday trading cycle.
If you are focusing on Last Look in forex, that concept concerns how counterparties may temporarily check or manage incoming orders during execution. It does not set a fixed duration for any forex session; session timing is about market hours and participation, not a broker-specific execution control.
Example checks and practical ways to verify timing
You can verify what “session length” means for your needs without assuming one universal answer:
- Use a market-hours reference: compare the hours shown by a reputable trading calendar to your instrument’s typical availability.
- Check your platform’s “market open” indicators: trading platforms often label when liquidity is expected to be higher.
- Compare daily activity: observe spreads and depth across the week; peaks often align with London/New York overlap.
These checks reduce uncertainty because session definitions are approximate and can differ by time zone and by holiday schedules.
Limitations and uncertainty
- No fixed session duration exists in forex the way it does for exchanges; “session” usually means a liquidity window, not a formal closing/opening rule.
- Clock hours are approximate: holiday calendars, daylight saving time shifts, and instrument-specific behavior can change when liquidity appears strongest.
- This is informational only: without real-time market data and without your specific broker/instrument settings, you cannot infer exact intraday conditions from session labels alone.