What SafeSearch does, and doesn't
With SafeSearch on, Google filters explicit images, videos and websites out of results. Bing, DuckDuckGo and YouTube (as Restricted Mode) have equivalents. It's a results filter: it doesn't stop you typing a site's address, and it doesn't block anything outside the search engine. It's a good layer on top of a site filter, not a replacement for one.
The toggle, and why it doesn't hold
Google's setting lives at google.com/safesearch and in every results page under Settings. Logged in, it follows your Google account; logged out, it follows the browser. Both are yours. A private window starts unfiltered. Bing and DuckDuckGo work the same way. The toggle is fine until the night you turn it off.
Enforcing it at DNS level
Search engines publish a way for networks and devices to force SafeSearch that doesn't depend on any setting: a special address that only ever serves filtered results.
- Google: when
www.google.com(and the country domains) resolve toforcesafesearch.google.com, every Google search from that device is filtered, in any browser, any profile, incognito included. - YouTube: resolving
www.youtube.comtorestrict.youtube.comforces strict Restricted Mode;restrictmoderate.youtube.comforces the moderate one. - Bing:
www.bing.com→strict.bing.com. - DuckDuckGo:
duckduckgo.com→safe.duckduckgo.com.
This is done by the DNS resolver the device uses, so it applies before any browser gets a say. It's the same layer as a DNS porn blocker, and the same resolvers usually offer both: DNS porn blockers explained.
What "enforced" looks like on the screen
Google shows a small lock: "SafeSearch is locked by your network administrator" or similar wording, and the setting can't be changed from the page. YouTube says Restricted Mode is enabled by the network. Image search returns filtered results only.
Setting it up on each device
You can do this yourself on a router or in a device's DNS settings if the resolver you pick supports it, with the usual limit: you set it, you can unset it. The router steps are in the router guide.
SELFCNTRL enforces safe search on every locked device as part of the filter: Google, Bing, DuckDuckGo and YouTube Restricted Mode, in every browser and in the apps, with no setting to toggle. On iPhone and iPad it's carried by a supervised profile that can't be removed and forbids VPNs; on Mac and Windows by the filter app tied to your account. Setup is ten minutes, once: the iPhone guide.
The honest limits
- SafeSearch is a classifier. It catches most explicit results, not all, and it occasionally over-filters. It's a layer, not a wall; the site filter underneath is what refuses the destination.
- Enforced YouTube Restricted Mode is strict: it hides comments and some mainstream videos too. Most people accept it; if you don't, you keep the site filter and drop the YouTube part.
- Search engines that don't publish an enforcement address can't be forced this way. Blocking them entirely at DNS is the alternative.
Side by side
| SafeSearch toggle | DNS enforcement you set | DNS enforcement, account-locked | |
|---|---|---|---|
| Filters Google, Bing, DDG results | Yes, per account/browser | Yes, device-wide | Yes, device-wide |
| Survives incognito / logout | No | Yes | Yes |
| YouTube Restricted Mode enforced | Separate toggle | Yes | Yes |
| Can be switched off tonight | Yes | Yes, in settings | No — 24-hour delay |
Questions
How do I lock SafeSearch so it can't be turned off?
Not from the Google settings page: that toggle is always yours. Enforce it at DNS level, by resolving www.google.com to forcesafesearch.google.com. Done by a resolver you can't change on impulse, it applies to every browser and can't be switched off from the page.
Does locked SafeSearch block Google Images completely?
It filters explicit results out of Google Images; it doesn't disable image search. If you want images.google.com gone entirely, block the domain at DNS level from your account.
Can I force YouTube Restricted Mode on iPhone?
Yes, at DNS level: www.youtube.com resolving to restrict.youtube.com enforces strict Restricted Mode in Safari, Chrome and the YouTube app. SELFCNTRL does this on every locked device.
Why does Google say SafeSearch is locked by my network?
Because the device is resolving Google through the enforcement address. That's the expected message when SafeSearch is enforced at DNS level, by a router, a resolver or a filter like SELFCNTRL.