Compare time zones at a glance

Time Pinboard lines up a 24-hour timeline for every city you add, all aligned to your home city. Read straight down a column and you see what time it is everywhere at that same moment. The shading shows real daylight for each place and date: light blue for day, a softer band for twilight, dark for night. Bold hours fall inside the usual 9 to 5 working day.

How to use it

• Add cities with the search box. It knows about 800 cities and every time zone; press Enter to add the highlighted one.
• Set your home city: the first row is home, and every other row is aligned to its day. Use "Make home" on any row to switch.
• Pick a date to plan ahead. Offsets, summer/winter time and sunrise and sunset are recalculated for that day.
• Pin a time by clicking any timeline. The pin shows up in every city with its local time, and "Copy" gives you a text version to paste into an invite.
• Share copies a link with your cities, date and pins, so others open exactly the same board.

Summer time and winter time

Many countries move their clocks forward one hour in spring (summer time, or daylight saving time) and back in autumn (winter, or standard time). They do not all switch on the same day. The United States and Canada change on the second Sunday of March and the first Sunday of November, while the European Union changes on the last Sunday of March and the last Sunday of October. For a few weeks each year the gap between New York and London is four hours instead of five.

The southern hemisphere runs the other way: Sydney, Santiago and Auckland are on summer time from roughly October to April. Most of Asia, Africa and South America do not change their clocks at all.

Time Pinboard reads each offset from your browser's time zone database for the exact date you pick, labels every city as summer or winter time, and warns you when a city's clocks change within the next two weeks.

Questions

Why does a city show a half-hour or 45-minute offset?

Some zones are not whole hours from UTC: India is UTC+5:30, Nepal UTC+5:45, Newfoundland UTC−3:30 and parts of Australia UTC+9:30. Their timelines show times like 14:30 so the columns still line up.

Where do sunrise and sunset come from?

They are calculated in your browser from each city's coordinates with the standard NOAA solar position formulas. Nothing is sent anywhere. Near the poles you will see full days of light or darkness around the solstices.

Is my board saved?

Yes, in your browser's local storage on this device. Nothing about your cities or pins is sent to a server. Use Share to move a board to another device.