Date-aware
The UTC offset is computed for that specific moment in the past — not with today’s rules.
Historical Time Zone Lookup
What time was it around the world when the Berlin Wall fell, or when man stepped on the Moon? Pick an event or enter your own moment — with historically accurate time zones.
The night the border checkpoints opened, 9 November 1989 (~23:00 in Berlin).
Famous events
Ready-made moments — the Berlin Wall, the Moon landing, the first iPhone and more — one click away.
Accurate history
Old DST rules and changed offsets are honoured via the IANA time-zone database.
Frequently asked questions
How do you compute the time for past dates?
We use the IANA time-zone database via the browser's Intl API. It holds the full history of UTC offsets and daylight-saving rules for every time zone, so results are correct for the past too.
Why is the offset sometimes different from today?
Countries have changed their time zones and DST rules over the years. Japan observed DST only in 1948–1951, and the EU only harmonised its rules in 1996, for example. When the historical offset differs from today's, we flag it with a "not today" badge.
Which time should I enter the event in?
Pick the time zone your entered time is in (or UTC), then enter the date and time. Or just pick one of the famous events — it sets the exact UTC moment automatically.
How far back does it work?
The tool is reliable for the 20th and 21st centuries, where historical time-zone data is accurate. For older dates (before ~1900) local time was often solar and standardisation varied.
Are the event times accurate?
The UTC instants for events are as accurate as the historical record allows; where the exact time is approximate, the description says so.
Is my data stored anywhere?
No. Every calculation happens entirely in your browser — nothing is sent or saved.