Time Zone Converter & World Clock

Understanding Time Zones: A Simple Guide

Time zones help us keep track of time around the world. The Earth is round and spins, so the sun shines on different parts at different times. That's why it's daytime in one place and nighttime in another!

There are 24 main time zones because there are 24 hours in a day. Each zone is roughly 15 degrees of longitude wide. The starting point is Greenwich Mean Time (GMT or UTC) in London.

Why Do We Have Time Zones?

Before the 1800s, every town used its own "solar time" based on the sun. But when trains and telegraphs came, this caused confusion—train schedules were a mess! In 1883, railroads in North America created standard time zones. Soon, the world followed.

What is Daylight Saving Time (DST)?

Many places "spring forward" clocks by 1 hour in summer to make evenings brighter and save energy. In fall, we "fall back" to standard time. This tool automatically handles DST!

The International Date Line

This imaginary line (near 180° longitude) is where the date changes. Cross it going west, and you gain a day—perfect for "time travel" fun!