As you may know, forex is open 24 hours, from 17h (EST) Sunday to 17H (EST) Friday. That’s 7 hours for Sunday from 17h to 00h, 4 x 24h Monday through Thursday and 17 hours for Friday, from 00h to 17h, for a total of 120 trading hours or the equivalent of 5 days.
However, the various market centers open and close at various hours as you can see below.
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This table is in EST.
Frankfurt is open from 2am to 10am.
London from 3am to 11am.
New-York from 8am to 4pm.
Sydney from 6pm to 2am.
Tokyo 7am to 3am.
In pink, I put the periods where 3 markets overlap:
From 2am to 3am: Frankfurt, Sydney, Tokyo
From 3am to 3am: Frankfurt, London, Tokyo
From 8am to 10am: Frankfurt, London, North America
In blue, you’ve got the periods when 2 markets overlap. And in green, only one market is active.
If you want to make yourself a table like this in your own time zone, simply convert your time from EST or go to this time zone converter:
http://forex.timezoneconverter.com/