WhatsApp uses your phone's time settings, not its own
WhatsApp does not have its own time format setting. The app displays time in whatever format your phone is set to use — 12-hour (with AM and PM) or 24-hour (military time). If you want WhatsApp to show 12-hour time, you change it in your phone's settings, not in WhatsApp itself.
This matters because WhatsApp shows timestamps on every message you send and receive. Those timestamps come directly from your device's clock. Once you switch your phone to 12-hour format, every app on your phone — including WhatsApp, email, text messages, and your calendar — will display time the same way.
Key Takeaways
- WhatsApp displays time in whatever format your phone's operating system is set to use, so you must change the setting on your device, not in the app.
- On Android, go to Settings, then System, then Date and Time, and toggle off "Use network-provided time" before selecting your preferred format.
- On iPhone, go to Settings, then General, then Date and Time, and turn off "Set Automatically" before choosing 12-hour or 24-hour time.
- After you change your phone's time format, close and reopen WhatsApp to see the change take effect in message timestamps.
How to change time format on Android
Open your phone's Settings app — this is usually a gear icon on your home screen or in your app drawer. Scroll down and tap System (on some Android phones this may be labeled About Phone or Device).
Look for Date and Time and tap it. You will see a toggle for Use network-provided time — turn this off. This step is important because if your phone automatically syncs time from your carrier, it may override your format choice. Below that, tap Time format and select 12-hour. Some Android versions call this 12-hour clock or AM/PM. Once you select it, close Settings and open WhatsApp again. Your message timestamps should now show times like 3:45 PM instead of 15:45.
How to change time format on iPhone
Open the Settings app and tap General. Scroll down and tap Date and Time. You will see a toggle labeled Set Automatically — turn this off. Like Android, this prevents your phone from overriding your choice.
Below that toggle, you will see 24-Hour Time. If this toggle is on, turn it off to use 12-hour format with AM and PM. If it is already off, your phone is set to 12-hour time. Close Settings, close WhatsApp completely (swipe it away from the app switcher), and reopen it. The timestamps should now display in 12-hour format.
Why the time format might not change when ready
WhatsApp caches — stores — the time format when you open it. If you change your phone's settings and WhatsApp is still running in the background, it may not pick up the change right away. The simplest fix is to close WhatsApp completely and reopen it.
On Android, swipe up from the bottom of the screen and hold to open the app switcher, find WhatsApp, and swipe it away. On iPhone, swipe up from the bottom or use the app switcher (swipe down from the top right on newer models), find WhatsApp, and swipe it up. Then tap WhatsApp again to reopen it. This forces the app to read your phone's current settings instead of using the old format it had stored in memory.
What happens to old message timestamps
Changing your phone's time format does not change timestamps on messages you received before the change. Those messages will update to the new format the next time you view them, but WhatsApp does not retroactively rewrite old data. The change applies going forward — new messages and new timestamps will display in your chosen format when ready.
If you scroll back through old conversations after changing the format, you may see a mix of old timestamps in the previous format and new ones in the current format. This is normal and does not indicate a problem with your phone or the app.
If your phone is set to 12-hour but WhatsApp still shows 24-hour time
First, restart your phone completely — not just close the app. Power it off, wait 10 seconds, and power it back on. This clears any cached settings that WhatsApp might be holding.
If that does not work, check that you actually turned off Use network-provided time (Android) or Set Automatically (iPhone). Your carrier or network can override your choice if this setting is on. Go back to Date and Time settings and confirm the toggle is off, then select 12-hour format again. If the problem persists, uninstall WhatsApp, restart your phone, and reinstall it from the Google Play Store (Android) or App Store (iPhone). This forces the app to read your phone's current settings fresh instead of using old cached data.
Frequently Asked Questions
Does changing to 12-hour time affect anything else on my phone?
Yes — every app and system function will switch to 12-hour format. Your calendar, email, text messages, and lock screen clock will all show AM and PM instead of 24-hour time. This is usually not a problem, but if you work in a field that uses 24-hour time (like aviation or military), you may want to keep 24-hour format on your phone.
Will my contacts see the time in a different format if I change mine?
No. The time format is a display setting on your phone only. When you send a message, the timestamp is based on your phone's clock, but the person receiving it sees it in whatever format their own phone is set to. You could be using 12-hour and they could be using 24-hour, and you would each see it your own way.
What if I only want WhatsApp to use 12-hour time, not my whole phone?
You cannot do this. WhatsApp does not have its own time format setting — it always uses your phone's system setting. If you want 24-hour time everywhere else but 12-hour in WhatsApp, you would have to change your phone's setting, use WhatsApp, then change it back, which is not practical.
Does this work the same way on WhatsApp Web or Desktop?
WhatsApp Web and Desktop use your computer's time format, not your phone's. To change the time format in WhatsApp Web, change your computer's date and time settings. On Windows, go to Settings, then Time and Language, then Date and Time. On Mac, go to System Preferences, then Date and Time.