IANA (Internet Assigned Numbers Authority) timezones are a global standard that help us keep track of the correct local time anywhere in the world. Instead of simply saying “GMT+2” or “UTC-5,” they use a name like “America/New_York” or “Europe/London”, which makes it easier to understand and avoids confusion.

Why Use IANA?

These timezones are useful because they do more than just tell the current hour. They also keep track of changes in local time, like daylight saving rules or when a country decides to change its official time. This means your calendar, phone, or computer can always show the right local time, even if laws or rules change.

A bit of history

Before global systems like IANA, it was very difficult to keep track of different clocks around the world. Every country — sometimes even every city — could make its own rules. The IANA database began as a community effort to collect this information and has grown into a worldwide standard. Today, almost every device that shows you the time depends on this system behind the scenes.

How it works

Each place on Earth has an identifier that usually follows the format Region/City. For example, Warsaw in Poland is labeled Europe/Warsaw. These labels are easier to use than just numbers because they take into account historical changes and rules about time shifts. If your city isn’t listed, it usually follows the same rules as the nearest major city.

Everyday benefits

Thanks to IANA timezones, you don’t have to worry about setting your watch or calendar when traveling abroad. Smartphones, computers, and even online meeting apps use these rules to make sure events are shown at the right local time. This helps avoid confusion when people in different countries plan calls, flights, or international events.

Why it matters

Protects you from missing events due to daylight saving changes.
Helps airlines, trains, and international meetings stay coordinated.
Makes it possible for phones and computers to “just know” the correct time.
Ensures history stays accurate — old timestamps won’t change when rules do.

Things to keep in mind

Time rules aren’t set in stone — governments can and do make changes. For example, some countries have stopped using daylight saving time completely. That’s why it’s important that devices update regularly, so your phone, laptop, or even your smart watch always stay correct.

A practical example

Imagine you schedule a video call between New York and London. If New York changes its daylight saving time rules, IANA’s system ensures your meeting still appears at the correct local hour on both sides. Without it, people could easily show up one hour too early or too late.

Where to learn more

If you’d like to dig deeper, you can search online for “IANA Timezone Database” or simply look at your device settings — when you select your city or region in a time settings menu, you are actually choosing an IANA timezone. It’s one of those invisible systems that quietly makes daily life smoother for everyone.