How to block a website in Firefox (2024)

There are many reasons to choose Mozilla Firefox over another web browser. One primary reason is security and privacy. Firefox has Enhanced Tracking Protection (ETP), which blocks intrusive trackers. On the other hand, Chromium-based web browsers are also secure, but they are a little less private. Nonetheless, both browsers have various settings that can change your experiences.

But even with Firefox's added protection, we should always take precautions. We do not want an untrustworthy website to access our information or have others open it from our device. So, to help give you peace of mind, we will teach you how to block a website in Firefox using any working phone and computer with Firefox installed. Although there are many ways to block websites on Firefox, we focused on the quickest and most reliable methods in our guide below.

Block a website using the Block Site add-on

The easiest way to block a Firefox website is to download an extension. Third parties create these extensions, so they are not guaranteed to work as intended and may pose risks. Generally, popular extensions are also the most trustworthy; if you are still unsure whether to try an extension, we recommend reading Mozilla's tips for assessing its safety.

In our tutorial below, we use the Block Site extension (add-on). Firefox has rated it a recommended extension because it meets the platform's standards. As a precaution, we've also tested it using a Windows desktop computer, as you will see in our steps.

1. Install the Block Site extension.

   

2. Click the Extensions icon next to your search bar (it looks like a puzzle piece).

   

3. Select the Block Site extension from your extension's list.

   

4. Enter the name and domain of the website you wish to block inside the text field. The box will auto-fill this field if you're already on the website's page (the one you want to block). Otherwise, you can overwrite the filled-in field.

   

5. Once you've entered the website you wish to block, click Ok.

   

If you plan to use this extension to block websites without visiting them firsthand (for example, blocking multiple websites), we recommend going into the Block Site extension options. From there, you can add a new rule or edit one from the list. To do this, perform the following:

1. Open Mozilla Firefox and click the Extensions icon at the top right corner.

   

2. Click the Gear icon to access the settings.

   

3. Select Options.

   

4. On this page, add a new hostname and select Add. It will add a new website using the existing rules; in this case, the rule is to block the domain name. You can also edit the rule, remove websites using the rule, and schedule unblocks. The extension provides a way to set a master password so anyone who knows that password can access blocked websites.

   

   See Also

   The best Firefox VPN extensions and add-ons 2024Best Mozilla Firefox VPN Browser Extensions in 2024Get the Best Mozilla Firefox VPN Extension | ExpressVPNBest VPNs for Firefox in 2024 : Fast, Safe & with Browser Extensions

Block a website using Leechblock NG on mobile

You can also install an add-on to block websites on Firefox mobile. Mobile extension support is still growing, and many useful add-ons, like uBlock Origin and Leechblock NG, are available. This tutorial covers how to block a website using the Leechblock NG add-on.

1. Install the Leechblock NG add-on; search for it on the Firefox add-ons page.
2. Tap Add to Firefox > Add.

   

   

3. Return to Firefox and navigate to the Three-dot icon, and tap Add-ons.
4. Select LeechBlock.

   

   

5. Inside the LeechBlock NG add-on page, tap Add Sites.
6. In the Block Add Sites text box, add the domain names of the websites you wish to block. Place a line break after each entry if you add multiple websites to this box.
7. Once you've finalized your blocked website list, tap Add Sites.

   

   

You can also set customization options for when, what, and how to block; we recommend switching to landscape view or using a tablet when changing these settings.

Block a website using Firefox's built-in settings

Blocking a website using Firefox's built-in settings also allows you to block sites from storing cookies and site data. If you've encountered the website before, we recommend deleting its cookies and data.

1. Open Mozilla Firefox on a computer and navigate to the Three-line menu.

   

2. Go to Settings.

   

3. Select Privacy & Security in the left panel.

   

4. Navigate to Cookies and Site Data and select Manage Exceptions.

   

5. Inside the Address of the website field, enter the website url you wish to block and then choose Block.

   

6. Select Save Changes.

   

After reviewing the Firefox mobile app, we noticed Mozilla does not have a built-in setting to block a website through the app's settings. To circumvent this, we recommend using the add-on method.

Block a website on Firefox by making a policy file

The methods above are the easiest ways to block a website, but you can also block websites by adding a policy file. It is akin to adding a banned website list, handy when you've already pre-established a series of websites you wish to block. Essentially, you're creating a rule on your computer, and every time you run Firefox, it checks the rule (in this case, it is "block," which will filter the websites). Some add-ons on Firefox can create this rule for you, but if you prefer to do this yourself, we walk you through the steps below.

Before proceeding, ensure you have admin privileges and permissions turned on.

1. On your computer, find the install location for Firefox; it is usually found in C:\Program Files\Mozilla Firefox or C:\Program Files (x86)\Mozilla Firefox.

   

2. Create a new folder and name it distribution. Leave that file open.
3. Open Microsoft Notepad and add (include the website in the block section)

   {"policies": {"WebsiteFilter": {"Block": ["*://*.nameofblockedwebsite.domainextension/*"]}}}

   

4. Name the file, policies.json, and change the Save as type to All files.
5. Save the policies.json file to the newly created distribution folder on your computer.

   

6. Restart Firefox; you should now see the listed website in the policies.json file blocked.

How to block a website on Firefox with iPad and iPhone using Content Restrictions

Using Apple's Content Restrictions setting on an iPad or iPhone, you can add specific websites or content types to block. Below, we walk you through the steps to block a website on Firefox using this method.

1. On your iPhone or iPad, go to Settings.

   

2. Tap Screen Time on the left panel of your settings.

   

3. Under Restrictions, tap Content & Privacy Restrictions.

   

4. Tap to toggle on Content & Privacy Restrictions.

   

5. Navigate to Content Restrictions (underneath Allowed Apps).

   

6. Scroll down and tap Web Content.

   

7. Tap Limit Adult Websites > Add website (under Never Allow).

   

8. Enter the URL of the website you wish to block.

   

Add security to your online surfing

It's good to be mindful of where you end up on the web. Some websites have security problems and malicious intent, and they can include trackers that relay personal information back to third parties. We want to avoid this altogether and make web browsing a safer practice for everyone. This is where a VPN for Firefox comes in handy; you can browse freely without leaking your IP. But even without a VPN, it is never a bad idea to think twice before you click on a random web link.