How to block online ads when browsing
Adverts can be used to track your online activity if you click on them, and can be annoying if you don’t want to see them.
Pop-up adverts can be particularly worrisome, with some redirecting you to malicious sites, which might contain malware, viruses, out-of-date software, or malicious code.
Blocking auto-playing video adverts and other irritations can make your browsing experience better, faster, and safer too. If you don’t want adverts to appear on web pages you view you can install ‘ad blockers’ as an extension or plug-in to your browser. Popular options include Ad Blocker, Ghostery, and uBlock Origin.
Some browsers come with in-built ad blockers. These browsers include Brave, LibreWolf, Opera, and Tor. Firefox's anti-tracking feature blocks some adverts. And whilst the DuckDuckGo browser doesn’t currently support extensions, it has some built-in data blocking which prevents many adverts.
But, Google is making efforts to prevent people from using this kind of plug-in, which interferes with a major revenue source. Its updates to Chrome have turned off some ad blocker extensions which users have installed, and the updates are likely to affect more ad blockers during 2025. This change by Google may also affect Opera and Microsoft’s Edge browsers because these run on the same underlying technology, called Chromium, which was created by Google.
Some ad blockers aren’t available for particular browsers. For example, uBlock Origin isn’t available for Safari because Apple (which owns Safari) has prevented it from being installed as an extension.
Which browsers won’t sell your data for advertising?
DuckDuckGo has adverts on its search pages and makes an income from private ads and affiliate partnerships. But as it doesn’t track or store your history, the adverts are related only to your current search e.g. if you type in walking boots, they will show you adverts for them, but these won’t appear the next day on an unrelated search.
Firefox is made by Mozilla, which is a non-profit organisation and doesn’t sell users’ browsing and search history to advertising companies.
Brave has a different take on adverts. It doesn’t gather or sell user data indiscriminately, but allows users to anonymously opt in to seeing adverts which have been pre-approved by Brave, which then earn the person rewards. The adverts on Brave don’t track users in the traditional way and no personal data is gathered. But they are a way of consumers supporting approved companies, which also helps Brave continue to offer its service.
Revenue from Ecosia's adverts is used to fund its climate activities particularly tree planting. Ecosia says that if you click on the adverts, this is not associated with a user profile. This means your clicks cannot be used to target ads to you either on Ecosia or elsewhere on the Internet. They partner with Microsoft to run the adverts.
Which browsers have the strongest privacy settings?
Personal data is a valuable commodity. Not only can it be sold to advertising companies to target you with specific adverts, but it may be stolen with the potential for identity theft and fraud.
Information can be recorded by cookies. These are small text files of information created when you visit a website, and they are stored on your device. Cookies are generally used for storing your preferences and other personalisation features. This includes things like passwords and language settings.
Cookies can be temporary, permanent, first party, or third party. If you regularly visit a weather page for example, a first party cookie may store your location so that you don’t have to type in the town name every time. It’s set by the owner of the weather website. In contrast, a third party cookie which is gathered while you are on the weather page has been placed there by other providers, primarily for tracking activity and advertising purposes.
Cookies can store enough data to potentially identify you without your consent. They are the main way that advertisers use to track your online activity so that they can target you with specific adverts. Cookies can be considered personal data in certain circumstances and are therefore subject to the GDPR regulations in the UK and EU. This includes US-based websites visited by someone in the UK. As a result of this you often have to either accept or decline different types of cookies (e.g. ‘essential’ or non-essential) when you visit a website.
Information can also be stored in your browser history, which lists all the sites and web pages you’ve been to. Sometimes it can be handy to look through your history if you need to find a website again, but it may be accessed by others, for example, by law enforcers, with different legislation in place in different countries. Those involved in sensitive work like activism may therefore want to limit the amount of information stored in their browser history.
The default privacy settings vary considerably depending on the browser you use. If you don’t want to spend ages going through all the settings and changing them to higher levels of privacy, use a browser which starts off at a higher level e.g. Brave, Epic or Tor.