How to turn on a Safari ad blocker on iPhone

Turn it on in the Settings app

1. Go to the Settings app on your iPhone.
2. Tap Apps, then tap Safari.
3. Tap Extensions, then tap the ad blocker.
4. Turn on Allow Extension.

Some blockers add more than one extension, for example one for ads and trackers and one for extra filters. Turn on each one the app asks for. If you have Safari profiles set up, Apple notes that you turn the extension on for each profile you want to use it with.

Turn it on from Safari

1. Open a web page in Safari.
2. Tap the page menu on the left side of the search field, then tap Manage Extensions.
3. Turn the ad blocker on.

The same list shows every extension you have installed, so you can check what each one does.

Check that it is working

1. Open the blocker app. A good blocker tells you whether Safari has its extension on. If it says something is still off, go back to the steps above.
2. Reload a page that had ads. Safari applies the rules to pages loaded after the change, so reload any page that was already open.
3. Use a test page. A test page asks the browser to load known ad and tracking addresses and counts how many Safari refused. Zero blocked means the extension is off in Safari.
4. Check the site is not excluded. Safari can turn an extension off for one website. Open the page menu, tap Manage Extensions and make sure the blocker is on for the site you are on.

Two Safari features do related jobs and work alongside a blocker. Block Pop-ups, in Settings > Apps > Safari, stops pop-up windows. The Privacy Report, in the page menu, lists trackers that Safari's Intelligent Tracking Prevention kept from following you across websites. Neither one removes ads from pages.

In Private Browsing, Apple notes that extensions with access to browsing data are turned off automatically. To use one there, turn it on in Settings > Apps > Safari > Extensions.

Allow a site when a page breaks

Blocking can stop a checkout, a login or a video from working. You can turn an extension off for one website without changing your overall Safari settings:

1. On the site, tap the page menu on the left side of the search field.
2. Tap Manage Extensions.
3. Turn the ad blocker off for this site, then reload the page.

Many blockers also keep their own list of allowed sites in the app, which is easier to review and undo later.

Where Ad & Popup Blocker: Clearpage helps

Ad & Popup Blocker: Clearpage adds a setup checker that names each Safari switch that is still off, with a button that opens the right place in Settings. Its status screen says whether blocking is on right now, which filter lists are loaded and when they were updated, and its test page counts what Safari blocks. Allowed sites and pause are in the app, free.

It lists its extensions as Clearpage Ads and Trackers and Clearpage Extra Filters in Safari's extension settings, which are the names to look for in the steps above. Blocking is free, with no limits.

Ad & Popup Blocker: Clearpage is coming soon to the App Store.