The time in Chicago

A live clock for Chicago in the United States, with the offset it is on right now, whether that is summer time, and the exact date it next moves.

Chicago across the year

Chicago runs on UTC-6 in winter and UTC-5 in summer, so the difference to you moves twice a year.

Worth knowing

Chicago is the home of US central time, the zone most often written "CST" when what is meant for half the year is CDT — one of the most common hours lost to a mis-typed abbreviation.

Questions

Where do the time zones come from?

From the IANA time-zone database, through your own browser and our build runtime rather than a list we typed out. This build was made against tzdata 2025b, which names 418 zones. We show that version because a stale time-zone database is a wrong answer that looks completely right.

Why does the difference between two time zones change during the year?

Because countries change their clocks on different dates. The United States moves in March and November, the European Union in the last weekends of March and October, and the southern hemisphere moves the opposite way entirely. For a few weeks each year the usual gap is an hour out, which is when most mis-scheduled calls happen.