What time is it there — and when does your meeting land for everyone?
DST-aware via your browser anchored to —
Live · every 30s
PresetsZones
Meeting planner
The day across your cities
green = comfortable hours (8am–8pm) · drag the marker to retime
Right now
Who is awake, and where the sun is
workingearlyeveningasleep
The dark half is computed from the sun's actual position for the date and time set above —
solar declination, the equation of time, and the terminator where the sun sits exactly on the
horizon. Move the time and the shadow moves with it. The coastlines are a five-degree
schematic for orientation and nothing more; the daylight is real.
Markets
Which exchanges are trading right now
Continuous session only — pre- and post-market are excluded, and Tokyo, Shanghai and
Hong Kong take a real lunch break that is shown separately. Weekends are the exchange's own,
not yours. Public holidays are not modelled, and session times change occasionally, so
check the exchange for anything that depends on it. Press Stock markets above to load
these cities as a comparison set.
Every pair
Which two cities are the problem
The whole list
Every IANA time zone, by region
Read from your browser's own copy of the IANA database, so it is complete and as current as
your device — nothing is shipped with the page that could go stale. Click any zone to
make it the anchor.
Field notes
How time zones work
How it works
Why the same clock reads differently
Every place keeps time as an offset from UTC, and that offset can change twice a year if the region
observes daylight saving. Pick a date and two places, and the conversion accounts for whatever rules applied
on that specific date — not just today's offset, which is why scheduling something six months out can
trip people up.
Worked example
A 9am meeting in London in January (GMT, UTC+0) lands at
1am in Los Angeles (PST, UTC−8) — an 8-hour gap. Schedule the same 9am London meeting
for July instead, and it's 1am Pacific Daylight Time, because both zones have
shifted for daylight saving, but not always by the same amount or on the same date.
Why do some countries not observe daylight saving?
Daylight saving mainly benefits places with a big seasonal swing in daylight hours — mid-to-high
latitudes. Countries near the equator see little seasonal daylight change, so many skip it entirely, while
others have abandoned it for practical or political reasons.
Why does the offset sometimes include a half hour?
Time zones are nominally 15° of longitude (1 hour) wide, but borders follow countries, not meridians. A
handful of places — India, Iran, parts of Australia — set their offset a half or even three-quarter hour
off the nearest whole hour, usually to sit in the middle of a wide country's longitude span.
How current are the daylight-saving rules used here?
They come from your browser's built-in time-zone database (the IANA tz database), which is updated
alongside your browser or operating system. That means the rules are as current as your device — a
long-unpatched browser could carry outdated transition dates.
Can a country change its time zone with little warning?
Yes — governments have moved daylight-saving start/end dates, or abolished DST altogether, sometimes with
only a few months' notice. For anything truly time-critical, especially in the near future, it's worth
double-checking against an official government or airline source.
Results are for reference only. Time-zone rules and daylight-saving dates change; double-check anything time-critical against an authoritative source.
Version history · 7 releases
v0.982026-07-28Welch two-sample t-test in Statistics. One tool, not three — two candidates already had the feature
v1.942026-08-09Time zones: 50 cities to 172, every IANA zone grouped by region, and a world map whose night side is computed from the sun's real position
v1.952026-08-09Time zones: searchable sortable city picker, zone and market presets, land tinted by UTC offset, and the remove button that sat on top of every clock
v1.962026-08-09World map colour ramp rebuilt in OKLCH and chosen by measurement — three offsets used to share one colour
v1.972026-08-0922 more cities in the time-zone catalogue, and Frankfurt stops being bolted on at runtime
v1.982026-08-09The sort control now orders the chosen cities too, not just the picker — four lists were each building their own order
v3.252026-08-16Profiling the rest of the tool pages found one outlier: the time-zone converter rebuilt 4,000 off-screen nodes on load and on every input
Releases in which this page changed, newest last. Derived from the archived copy of every release, not from notes written afterwards — so it reflects what actually shipped. Site-wide passes are left out; they are in the full changelog.