DNS filter or blocker app on iPhone? What each one blocks

A DNS filter and a blocker app do different jobs; use both. A free DNS filter (CleanBrowsing, OpenDNS FamilyShield, Cloudflare’s 1.1.1.1 for Families) blocks adult sites by name in every app, but typed into Wi-Fi settings it covers only that network, not mobile data, and a profile or app can be removed by anyone who can open Settings. Apple’s Screen Time filter and a Safari blocker live on the phone and work on every network, and the Screen Time filter sits behind a passcode. Our pick: Limit Adult Websites plus The Blocker (free in Safari; Pro’s Strong protection for every browser), with a DNS filter on the home router as an extra layer.

Written by the developer of The Blocker, one of the tools here, so we have a bias. The Blocker is not affiliated with CleanBrowsing, Cisco (OpenDNS) or Cloudflare, and it uses no DNS or VPN of its own. Facts checked 22 October 2026 on each provider’s official pages and Apple’s guides; we did not test the DNS services. Menu names can differ with your iOS version and language.

How a DNS filter blocks adult sites

Before your iPhone opens a website, it asks a DNS server for the site’s address. A DNS filter refuses to answer for blocked sites; Cloudflare, for example, “returns the address 0.0.0.0 instead of the real address” (Cloudflare). This happens below the browser, so it reaches every app.

It works by site name only, so it can’t tell a safe page from an unsafe one on the same site: CleanBrowsing’s Family filter blocks “mixed content sites (like Reddit)” as a whole (CleanBrowsing). And the DNS company answers every lookup your phone makes, so read its privacy policy.

Three free DNS filters for adult content

CleanBrowsing Family filter “blocks access to all adult, pornographic and explicit sites”, plus proxy and VPN domains used to get around filters. The free tier needs no account but is throttled and has no support; its addresses are 185.228.168.168 and 185.228.169.168 (filters). On iPhone it recommends a configuration profile, or its app, which adds a VPN configuration (setup). It says the profile “works system-wide on all networks (Wi-Fi, cellular, VPN)” and “can be removed at any time from device settings” (profile).

OpenDNS FamilyShield, from Cisco, is “preconfigured to block adult content”, with “no sign-up required” (OpenDNS). Its nameservers are 208.67.222.123 and 208.67.220.123, and its guide recommends home routers and has no iPhone section (setup guide).

Cloudflare 1.1.1.1 for Families blocks malware and adult content at 1.1.1.3 and 1.0.0.3 (Cloudflare). Cloudflare calls it “Free protection for your home Internet” (1.1.1.1 for Families). On iPhone it recommends its free 1.1.1.1 app, which installs a VPN profile; turn Families on under Advanced › Connection options › DNS settings › 1.1.1.1 for Families (Cloudflare for iOS).

Wi-Fi only or every network: the mobile-data gap

On iPhone, the manual DNS setting lives inside each Wi-Fi network: Settings › Wi-Fi › ⓘ › Configure DNS (Apple). Cloudflare says manual setup “only applies to the Wi-Fi network you are currently connected to” and “does not work for cellular connections” (Cloudflare). So a filter typed into Wi-Fi settings stops when you leave the house. A profile or an app closes that gap; a router filter covers your home Wi-Fi only.

One more gap: with iCloud Private Relay (part of iCloud+) on, Apple says your DNS records for Safari browsing “are encrypted, so neither party can see the address of the website you’re trying to visit” (Apple). A filter on your Wi-Fi or router may not see those lookups. Apple doesn’t say how Private Relay treats a DNS profile or app.

How easy each one is to switch off

CleanBrowsing itself warns that anyone with access to network settings can switch DNS servers, “instantly bypassing your content filter” (CleanBrowsing). Installed profiles are listed in Settings › General › VPN & Device Management, and deleting one deletes its settings (Apple). A DNS app can be switched off, and another VPN app can carry DNS past the filter, “completely bypassing your network’s DNS configuration” (CleanBrowsing). Limit Adult Websites is different: once a Screen Time passcode is set, changing it needs that passcode (Apple).

We found no Apple page saying Screen Time stops a DNS profile from being deleted or the Wi-Fi DNS from being changed. So on your own iPhone, treat a DNS filter as an extra layer, not the lock.

Where a blocker app and Screen Time fit

Limit Adult Websites is built into iOS and free. Apple says it “limits access to many adult websites automatically” and can restrict “Safari and third-party apps” (Apple). It lives on the phone, whatever the network, behind the Screen Time passcode. On iOS 26: Settings › Screen Time › Content & Privacy Restrictions › App Store, Media, Web, & Games › Web Content › Limit Adult Websites (Apple).

The Blocker is a Safari content blocker. The free version blocks adult sites in Safari and in pages apps open in a Safari view, by whole sites and by words in site names, plus 10 sites of your own. It doesn’t reach Chrome or the built-in browsers of apps like Instagram; that needs Pro.

Strong protection (Pro) uses the same Screen Time web filter as Limit Adult Websites (Apple Developer) to block adult sites and up to 50 of your own sites in every browser and in links you open inside apps like Instagram or X. It can also stop The Blocker from being deleted, keep apps you choose closed, and start a one-hour Hard moment. It doesn’t filter feeds inside apps. Pro is $4.99 a month, $29.99 a year or $49.99 once in the US; the App Store shows your local price. See Strong protection.

Side by side

Topic	DNS filter	Safari content blocker (The Blocker, free)	Screen Time web filter (Limit Adult Websites; Strong protection in Pro)
How it blocks	Refuses to look up blocked site names	Safari applies a rule list: whole sites and words in site names	iOS applies Apple’s adult filter, plus sites you list
Where it works	Wi-Fi setting: that network only. Profile or app: every network	Safari and Safari views in apps, on any network	The phone itself, on any network. Strong protection: every browser and links inside apps
Inside other apps	Any app using the phone’s DNS, whole sites only	No	Web pages only; Blocked apps (Pro) keeps apps you pick closed
Switching it off	Easy: reset the Wi-Fi DNS, delete the profile or turn the app off	In Safari’s settings, unless Limit Adult Websites is on	Limit Adult Websites needs the Screen Time passcode; Strong protection can be turned off in the app, after your delay

The setup we suggest

Turn on The Blocker in Safari first, in every Safari profile you use.
Turn on Limit Adult Websites; The Blocker’s setup notes this also keeps Safari extensions switched on.
Ask someone you trust to set the Screen Time passcode, and agree whose Apple Account recovers it. See how to make a blocker hard to turn off.
Other browsers: remove them, or turn on Strong protection. See blocking adult sites in Chrome.
Optional: a DNS filter on your home router, or as a profile on the phone.

If Apple’s filter seems to let sites through, read Limit Adult Websites not working. All no-cost options: free ways to block porn on iPhone.

Questions people ask

What is the best DNS for blocking adult content on iPhone?

There is no single best one, and we have not tested which blocks more. CleanBrowsing’s Family filter also blocks proxy and VPN domains; OpenDNS FamilyShield suits a home router; Cloudflare’s 1.1.1.1 for Families app also covers mobile data. How you set it up matters most: a profile or app covers every network, a Wi-Fi setting covers one.

Does a DNS filter work on mobile data?

Not if you type it into Wi-Fi settings: Cloudflare says manual setup “does not work for cellular connections” (Cloudflare). A DNS profile or a DNS app covers mobile data too.

Is Cloudflare’s family DNS better than a blocker app?

They do different things. 1.1.1.1 for Families is free and filters every app on the networks where it is set, but can be switched off without a passcode. Apple’s Screen Time filter works on every network behind a passcode someone else keeps, and a blocker app adds its own layer on the phone. Using both covers more.

Can I use a DNS filter and The Blocker together?

Yes. The Blocker doesn’t use a VPN or change DNS, so a DNS filter can run alongside it. We have not tested every combination; if a site you need is blocked, check which layer blocks it.

Sources

Download for iPhone

Back to The Blocker