How to Clear DNS Cache on iPhone and Android
To clear the DNS cache on an iPhone, turn on Airplane Mode for 15 seconds and turn it back off, this flushes the network cache. On Android, open Google Chrome, type chrome://net-internals/#dns into the address bar, and tap 'Clear host cache'. Alternatively, rebooting any mobile device will completely clear its temporary DNS records.
Cellular DNS Caching vs Wi-Fi Router Caching
Mobile devices maintain DNS caches independently from your router:
Cache Location | Cleared By | Affects |
iPhone OS cache | Airplane Mode toggle / Reboot | All apps and browsers |
Android OS cache | Reboot | All apps and browsers |
Chrome mobile cache | chrome://net-internals/#dns | Chrome only |
Wi-Fi router cache | Router reboot | All devices on network |
Cellular carrier cache | Carrier-side, not user-controlled | Automatic TTL expiry |
The key insight: Your computer loading the new site while your iPhone still shows the old one means the phone's local cache is stale, not the DNS records themselves.
Your DNS records are correct. The phone just hasn't checked them lately.
Why It Matters: Accurate Mobile Migration Testing
After changing hosting providers or updating IP addresses, stale mobile caches cause:
- Testing the wrong server while believing migration is complete
- Customers on mobile seeing broken or outdated versions of your site
- Ghost redirects from old configurations appearing only on certain devices
Confirming your DNS records are correct first via NameSilo's DNS Manager eliminates the records as the cause. If desktop resolves correctly but mobile doesn't, it's always local cache.
Implementation Steps (iOS): Clear iPhone DNS Cache
Method 1: Airplane Mode Toggle (Fastest)
- Open Settings
- Toggle Airplane Mode ON
- Wait 15 seconds
- Toggle Airplane Mode OFF
This drops all network connections and forces iOS to rebuild them from scratch, discarding cached DNS entries. No data is lost, Wi-Fi reconnects automatically.
This is the go-to method. It takes 15 seconds, loses nothing, and works on every iPhone model without navigating deep menus.
Method 2: Reboot A full power cycle clears all DNS caches completely. Slower but equally effective.
Method 3: Reset Network Settings (Nuclear Option) For stubborn caching issues that persist after Airplane Mode:
Settings → General → Transfer or Reset iPhone → Reset → Reset Network Settings
Warning: This deletes all saved Wi-Fi passwords, VPN configurations, and Bluetooth pairings. Use only when Methods 1 and 2 fail.
Implementation Steps (Android): Clear Android DNS Cache
Method 1: Chrome Browser Cache
- Open Chrome on your Android device
- Type chrome://net-internals/#dns in the address bar
- Tap Clear host cache
- Also tap chrome://net-internals/#sockets → Flush socket pools
This clears Chrome's internal DNS table but not system-level cache.
Method 2: Reboot Android doesn't offer a dedicated DNS flush menu. A full reboot is the most complete solution for system-level cache.
Method 3: Toggle Airplane Mode Same as iOS, effective on Android as well for a quick network reset.
Common Mistakes
Clearing Safari or Chrome history and cookies: This deletes browsing history, saved passwords, and session logins, but does nothing to DNS routing. You'll be logged out of websites while still seeing the old IP address.
DNS cache and browser history are completely separate systems.
Testing migration from the same device without flushing: Every test on a cached device is meaningless. Flush between tests.
What This Means for You
Before troubleshooting your phone, verify your DNS records are correct in NameSilo's DNS Manager. If records show correctly globally, the issue is your device cache, not propagation.
Frequently Asked Questions
How do I flush DNS on my iPhone?
Toggle Airplane Mode on for 15 seconds, then off.
Does Airplane Mode clear DNS cache?
Yes. It drops and rebuilds all network connections.
How do I clear DNS cache on Android?
Chrome: chrome://net-internals/#dns → Clear host cache. Or reboot.
Why is my phone showing an old version of a website?
Stale local DNS cache mapping old IP to domain.
Does clearing Safari cookies clear DNS?
No. Cookies and DNS are completely separate systems.
How long do phones cache DNS?
Usually minutes to hours, depending on the record's TTL.
What is chrome://net-internals/#dns?
Chrome's internal DNS diagnostic and flush page.
How do I change DNS servers on iOS?
Settings → Wi-Fi → tap network → Configure DNS → Manual.
NameSilo Staff
The NameSilo staff of writers worked together on this post. It was a combination of efforts from our passionate writers that produce content to educate and provide insights for all our readers.
