Open World Clock FAQ
Short, factual answers to what people ask most. If yours isn’t here, open an issue on GitHub and I’ll answer it there.
- Updated 25 September 2026
- Version 1.3.0
The basics
What is Open World Clock?
The best world clock for Windows, and it’s completely free. It shows the time in the cities you choose, turns each city’s card light or dark at its real sunrise and sunset, converts any time across all of them, finds meeting overlaps and shows day and night on a world map. See every feature.
Is it really free?
Yes, with no strings attached: no price, no ads, no account, no in-app purchases and no upsell. You shouldn’t have to pay for good software like this. The code is open source under the MIT License, so anyone can read it. Tips on Ko-fi are optional and change nothing in the app.
Does it work offline?
Yes. Time zone rules are built into the app, and sunrise and sunset are calculated on your PC. When a country changes its clocks, the new rules come with an app update. The app makes no network requests of its own.
What data does it collect?
None. Your cities and settings stay in one file under %APPDATA%\Open World Clock and never leave your PC. The privacy policy has the details, including what this website measures.
Installing
Which Windows versions and processors does it support?
Windows 10 and Windows 11, on x64 and ARM64. The Store build needs Windows 10 version 1809 or later and runs natively on both. The installer and the portable exe are x64 only, so on an ARM64 PC use the Store.
How do I install it?
Get it from the Microsoft Store, or run winget install 9N88FR8M81BM -s msstore. There’s also an installer and a portable exe on GitHub Releases. The download page walks through each one. Can’t install software on your PC? You can try it right on the home page, in your browser.
Why does Windows say “Windows protected your PC”?
The installer and the portable exe aren’t code-signed yet, so SmartScreen warns the first time you run them. Select More info, then Run anyway. The Microsoft Store build doesn’t show this.
Does it need admin rights?
No. The installer installs for your Windows user only, the portable exe installs nothing, and the Store handles its own install.
Using it
Can it stay on top of other windows?
Yes. Pin it above all windows, like a desktop widget, or let it sit with the rest. It’s frameless and translucent, with three layouts: strip, compact and vertical.
How do I convert a time between time zones?
Type a time like 3pm, 9:30 or 15h30, pick the city it belongs to, and every card shows the matching time, with +1 day or -1 day where the date changes. Or turn the mouse wheel over any card to move every clock in 15-minute steps. More on the time zone converter page.
Does it handle daylight saving time?
Yes. Each conversion uses the rules for its own date, the card shows a note in the week before clocks change, and a time that falls in the spring-forward gap moves forward the way Windows does.
Can it help schedule meetings across time zones?
Yes. The meeting planner shows a 24-hour row per city, with working hours and days you set per city, night shifts included, and labels the shared window, for example “3 h overlap”.
Limits, and who makes it
Does it have alarms, timers or weather?
No. The Clock app that comes with Windows covers alarms and timers well, and weather would need the internet, which the app doesn’t use. Here’s how the two compare.
Is there a Mac, Linux, Android or iPhone version?
Not yet. It runs on Windows only. An iPhone version with Home Screen, Lock Screen and StandBy widgets is in the works, with no release date.
Who makes it?
I do. I’m João Carvalho, and I build it on my own. It isn’t affiliated with Microsoft. Bug reports and ideas are welcome as GitHub issues.
More about Open World Clock
Put the world on your desktop
Completely free for Windows 10 and 11. Open source, no account, no ads, no telemetry.