The question that looks simple
What time of day do I trade worst? It sounds like the easiest thing a journal could answer, and it is the one most likely to be quietly wrong.
The reason is that the timestamps in a trade history are not in your timezone, are usually not in UTC, and carry no marker saying which. Every hour-of-day chart built on an import inherits that ambiguity, and none of them mention it.
Two things this section covers
Server time — why your statement is stamped in the broker's time, how far off that can be, and what it does to any analysis by hour. This is the practical one: it affects numbers you may already be looking at.
Sessions and overlaps — when the major sessions actually run, why the overlaps matter more than the sessions themselves, and how daylight saving quietly shifts everything twice a year while local opening times stay put.
What this section deliberately does not contain
No table of exact opening hours per exchange, no holiday calendar, and no contract specifications.
Those change — holidays annually, contract details at the exchange's discretion, session hours whenever a venue adjusts them — and a page publishing them without a checked date becomes wrong silently, which is the failure this whole site is built to avoid. Where we eventually publish such data it will carry a date per row, and until then we would rather send you to the venue's own page than repeat a number we have not verified.
What is here instead is the part that does not expire: how time works in your data, and why the same trade can appear at two different hours depending on who is reading the file.
The short version
If you take one thing: before trusting any by-hour analysis, find out what timezone your broker's server runs on. It is usually stated in the platform, in the account details or the market watch. Compare it to your own clock once, write the offset down, and every hour-based statistic you ever read becomes interpretable.
Without that number, "I trade worst at 3pm" is a fact about a server you have never met.