How far clocks run from the sun
On standard time, clocks in 233 of the 312 zones run ahead of local mean solar time at the zone’s reference city, so clock noon comes before the sun is highest. In 63 zones the gap is an hour or more, and the median gap, ahead or behind, is 27 minutes.
How the gap is measured
Local mean solar time at a place is its longitude multiplied by four minutes: a city at 15 degrees east is one hour ahead of Greenwich by the sun. The gap shown here is the zone’s standard time minus that solar time, at the coordinates the tz database gives for the zone’s reference city. A positive gap means the clock is ahead of the sun; a negative one means it is behind. The figure ignores the small seasonal wobble known as the equation of time, and it describes the reference city only. A zone that stretches far east or west has a different gap at each end.
The largest gaps between clock and sun
Standard time minus mean solar time at the reference city, in hours and minutes. Amber: clocks ahead of the sun; blue: behind.
Where clocks run furthest ahead
8 of the ten largest gaps are in north-western North America or southern South America, where zones keep a standard time that matches the sun at places well to their east. Inuvik leads with 2 hours 55 minutes: its record moved to UTC−6 as standard time in 2026, which added an hour to a gap that was already large.
| Zone | Country | Clock ahead of the sun |
|---|---|---|
| Inuvik | Canada | +2 h 55 min |
| Dawson | Canada | +2 h 18 min |
| Nome | United States | +2 h 2 min |
| Whitehorse | Canada | +2 h |
| Coyhaique | Chile | +1 h 48 min |
| Davis Station | Antarctica | +1 h 48 min |
| Adak | United States | +1 h 47 min |
| Punta Arenas | Chile | +1 h 44 min |
| Aqtau | Kazakhstan | +1 h 39 min |
| Rio Gallegos | Argentina | +1 h 37 min |
Where clocks run behind
Clocks behind the sun are less common, and the gaps are smaller. Apart from Vostok Station, a research station whose standard time was moved in 2023, the largest are in north-eastern Brazil, where Recife runs 40 minutes behind the sun. Only 5 zones in all run more than 30 minutes behind the sun, against 139 that run more than 30 minutes ahead.
Summer time widens the gap
For zones that still change their clocks, summer time adds an hour to the gap for part of the year. Of the 101 zones with seasonal changes under the current rules, 9 reach two hours or more ahead of the sun in summer. Madrid is a European example: on standard time its clock is 1 hour 15 minutes ahead of mean solar time at Madrid, and in summer 2 hours 15 minutes. United Kingdom sits almost exactly on its solar time in winter, as the Greenwich meridian runs through the city.
Large countries, one clock
The figures depend on the reference city, so a single zone covering a wide country can hide large gaps. China’s main zone is measured at Shanghai, where the clock runs 6 minutes behind the sun. The database also has a separate zone, Ürümqi, for Xinjiang time, UTC+6; at Ürümqi that clock is 10 minutes ahead of the sun.
The gap in well-known cities
Most large cities sit within an hour of their solar time. On standard time, New York runs 4 minutes behind the sun, Chicago runs 9 minutes behind the sun, Los Angeles runs 7 minutes behind the sun, Mexico City runs 37 minutes ahead of the sun, São Paulo runs 6 minutes ahead of the sun, Paris runs 51 minutes ahead of the sun, Berlin runs 7 minutes ahead of the sun, Moscow runs 30 minutes ahead of the sun, Lagos runs 46 minutes ahead of the sun, Tokyo runs 19 minutes behind the sun and Sydney runs 5 minutes behind the sun. These figures are for the reference city of each zone and use standard time; in summer, add the seasonal hour where it applies. A city at the eastern edge of its zone sees the sun earlier by the clock than one at the western edge, so two cities on the same clock can have gaps that differ by an hour or more.
Overall, 139 zones run more than 30 minutes ahead of the sun on standard time. Under the current rules, summer time takes 97 of the zones that still change their clocks to more than 30 minutes ahead during the summer months.
Across the date line
6 zones in the Pacific keep a date one day ahead of their solar time: their clocks are set from the western side of the date line while they lie east of the 180th meridian. In time of day the gap is small, for example 29 minutes at Kiritimati, but the calendar runs a full day ahead of the sun. Each of these zones is listed on its own page with its exact figure.
Source: IANA Time Zone Database, release 2026f (public domain), computed by this site; see about the data for definitions. Look up any zone in the converter.