I've been a software developer for over 10 years, seeing first-hand how technology is re-wiring people in harmful ways. As a result, I've spent a considerable amount of effort evaluating the best porn blocking DNS Filters that I could find, even going so far as to build my own tools!

The problem with most DNS Filters is that they tend to focus on protecting users from malicious websites and Ad tracking --  blocking Porn is usually not their central focus. As a result, most DNS Filters aren't capable of effectively doing the job of blocking adult content.

I'll walk you through how to select the right filter based on common use cases in 2024.

What to Look for when picking a DNS Porn Blocker

After years in the Cybersecurity industry and trying to come up with the right balance between protecting myself, loved ones, and personal devices from addictive content and online security threats, here is how I assess DNS Filters that claim to block porn:

1. How customizable is the content blocking policy?
   
2. What are the bypass prevention techniques?
3. Is it possible to schedule blocks?
   
4. Can you personalize a content policy to apply rules differently based on individual preferences? 
5. Does it protect against both online threats and addictive content?
   

Customizing DNS Content Policies to Block Porn

A DNS Filtering service classifies websites and online apps into different categories based on their content and purpose.

A highly customizable Content Policy is essential for an effective DNS porn blocker and it's one of the main reasons that I had to create my own solution with Tech Lockdown.

The ability to refine categories to hone in on different types of problematic content is critical, but most services give you only a few categories to choose from.

For example, you might get access to a general Adult Content category, but this may not be restrictive enough for some people.

Instead, I want to have a much wider selection to create my own Adult Content category. So this is the approach I made when crafting my own DNS Filtering solution.

You can create a rule in your DNS Content Policy . I've named my rule Adult content.

Then, I choose from over 200 categorization options to customize what I want to block.

Preventing Bypass of DNS Filter Porn Blocking Rules

You wouldn't consider bypassing your own security or privacy tools, but DNS Filters that focus on blocking porn need to have bypass prevention features as a primary focus. Some people will go through great lengths to access addictive content!

Furthermore, DNS filters that block porn are typically focused on helping parents monitor and protect their kids. This might be the focus for some people, but I want to also protect myself from harmful and addictive online content.

1. Prevent easily logging in and disabling blocking rules.
2. Block VPNs and Proxies.
   
3. Allow blocking entire categories and whitelisting specific platforms. This allows you to account for "gray-area" websites that host a variety of content, which can be used to bypass DNS Filtering.
   

One of the most common bypass techniques for any kind of system that blocks addicting content is to simply login and disable a blocking rule.

So how do people solve for this so that they don't disable their block rules?

The most common workaround is to block access to your own filtering account so that you can't even login.

This is quite limiting and risky! What if you find new things that need to be blocked? Now you can't login and make those necessary changes and your blocking system has a serious loophole.

My solution to this problem was to design Tech Lockdown with lockable profiles.

When your profile is locked, making a Content Policy less restrictive is prevented but you can still make it more restrictive.

Another common bypass technique is to use a Proxy or VPN to prevent the filter from working properly to identify the website you are viewing. 

One way to handle this is to block Anonymizers, which also allows you to block VPNs and proxies . For example, I can use my Tech Lockdown Content Policy to block the Anonymizer category to handle this:

The other scenario you have to account for is someone using a platform like Twitter to access adult content.

You can't use a DNS Filtering service to block specific pages within a website. If someone visits twitter.com, the DNS Filter just sees that a social media website is being accessed.

The best way to account for this is to block an entire category by default and then selectively whitelist the platforms that are safe.

For example, with Tech Lockdown you can block the entire social media category, but allow access to Linkedin:

If you are blocking content for someone else, you'll have a chance to review a social media website that isn't in your whitelist instead of waiting to find out that it needs to be blocked.

Blocking Content for a specific Person

What if you want to block Facebook for a specific person, not your entire household?

I struggled to find a DNS Filtering service that solved for this common scenario. Usually you apply the same Content Policy to everyone in your household

Lack of personalized content policies is one of the main reasons I designed my own solution. I can do this with my DNS Content Policy . First, I'll create a block rule for a specific person. 

Then, use the App selector to select the Facebook app. In fact, I can even specifically select Facebook Messenger.

Once I select the Facebook app in this block rule, Facebook will be comprehensively blocked in the browser as well as the native smartphone app.

Scheduling Social Media, Video Streaming, and Internet Usage

A less common, but critically important feature that every porn blocking DNS Filter should have is the ability to schedule content blocking rules.

People focused on blocking porn often discover that they need to reduce time spent on the internet in other ways as well. One of the best ways to do this is with scheduled DNS block rules.

Here are some scheduling considerations:

1. Social Media
2. Video Streaming websites like YouTube
3. The entire internet (at night)

I was never able to find a DNS Filter that let me schedule rules in a way that was useful, so I've placed a specific emphasis on this feature with Tech Lockdown. Here is how I schedule rules:

I first edit my  DNS Content Policy to select a category, app, or domain that should be blocked.

Then, assign a schedule to that rule. You can pick days of the week and time ranges to apply the block.

I personally use this approach to limit my access to news and social media to my lunch break.

Otherwise, I always block these categories and apps.

You can also set internet shut off times  at night, which is great idea if you are focused on blocking pornography and addictive content with a DNS Filter:

This approach is ideal because it takes 4g/5g connections into account, not just your home Wifi. 

This doesn't technically turn off your internet, but it lets you block access to everything other than what you specifically whitelist.

For example, I use security cameras at my house that need Wifi to work properly, so I add those services to my allowlist.

Balancing Security with Addictive Content Blocking

With typical DNS content blocking solutions and internet firewalls, you usually have to choose between blocking pornographic content or securing your personal devices from online threats.

As someone with a background in cybersecurity, I'm not willing to make this tradeoff - I want both! 

That's why I ensured the core capability for my DNS Filtering solution was accurate and timely categorization of websites and apps. This means that you can block harmful and addicting content while also handling security and privacy concerns.

Comparing the Top Porn Blocking DNS Filters

If you're an individual trying to quit porn or a parent protecting your household from harmful content, you're looking for a DNS Filter with the following attributes:

• It's effective at blocking and identifying adult content.
• The content policy provides a wide range of customization, like scoping a rule to a schedule or specific person and choosing from many different apps and categories.
  
• It emphasizes bypass prevention.
• It can be configured on mobile/roaming devices so that it works on any internet connection.
• It's fast, reliable, and works consistently.

Blocking Porn with Tech Lockdown DNS Filtering

After years of trying to find a DNS Filtering service that I could use long-term, I ended up having to design my own solution to meet all the requirements that I had.

Tech Lockdown integrates with the well-known and incredibly powerful Cloudflare service.

Large enterprise companies depend on Cloudflare for their critical Cybersecurity needs, so billions of dollars are invested into their infrastructure.

Cloudflare powers around 80% of the internet. Remember earlier how I mentioned that accurate and timely categorization was important for a porn blocking DNS service? Cloudflare is unmatched when it comes to identifying and tagging domains.

But here's the problem: Cloudflare isn't really designed for personal use and it requires a lot of technical ability to use properly.

This is where Tech Lockdown comes in: you can leverage the powerful Cloudflare capability with additional features that make it more applicable to your needs at home, especially when trying to block porn.

Here are some notable features:

1. Highly customizable Content Policy: select from over 200 categories and apps or add your own list of domains to block. 
2. Assign a schedule to individual content policy rules
3. Scope a rule to a specific person who is sharing your DNS Filter
4. Lock your Tech Lockdown profile to prevent making your content policy less restrictive

When blocking porn with a DNS Filter, accountability is an important piece. While locking your profile is a preventative measure, you can go further if you are collaborating with a partner using our History feature.

It increases accountability by providing an immutable trail of breadcrumbs that show changes on your account.

OpenDNS Family Shield

OpenDNS Family Shield is one of the oldest and well-known DNS Filters for blocking porn. 

Pros

• Free
• Setup is pretty simple - you simply point your primary and secondary DNS Servers on your router or device to the  FamilyShield  IP addresses and you're good to go.

Cons

• It blocks well-known adult content websites, but it's trivial to find unblocked websites.
• You can't customize the categories that are blocked and you can't manage your own list of allowed or blocked websites.
  
• Does not use machine learning to identify adult content in real time, so the blocklists are quite outdated.
• It does not strictly force search engines to use safe search mode or block search engines that do not support a safe search mode.

Conclusion

Although it is free to setup OpenDNS , it's not an effective content filter and we don't recommend using it as a long term solution. If you're setting up a new computer or home network and want to quickly block adult content, it's quick and easy to point to FamilyShield to at least have some protection. However, we would recommend quickly replacing it with a better solution once you have the time.

OpenDNS Home

OpenDNS Home is similar to FamilyShield, but you can customize the blocking settings.

Pros

Same benefits is FamilyShield plus:

• Customizable blocking, which might be useful if you want to block some torrenting websites or other unsuitable content types and manage your own website blocklist.

Cons

Similar cons to FamilyShield plus:

• It's actually harder to install compared to FamilyShield. Before pointing the primary and secondary DNS servers to OpenDNS Home, you must add your home network's IP address to the OpenDNS dashboard. This is a step you don't have to do with FamilyShield, but it's absolutely critical.
• Now that you have to enter an IP address into OpenDNS, you open yourself up to significant reliability issues. Sometimes your IP address changes -- when your home network IP address changes (like when you reset your router), OpenDNS will completely stop working. To solve for this, OpenDNS provides an IP updater tool that you need to download and install on a computer that you use regularly at your home. The obvious issue with this is that now it's really easy to break OpenDNS. Your computer's IP address might not match your home network (for various reasons, but I won't go into this). This means that the updater client will send the wrong IP to OpenDNS, completely breaking the filter. Also, you can easily disable the IP updater on your computer if you want to break filtering on your entire home network.An ideal customizable web content filter will allow you to use a hostname instead of an IP address to connect your home network to the filtering service. This way you can send IP updates via your router instead of a specific computer, insuring that content filtering always stays enabled.
• An ideal customizable web content filter will allow you to use a hostname instead of an IP address to connect your home network to the filtering service. This way you can send IP updates via your router instead of a specific computer, insuring that content filtering always stays enabled.
• Although you can add individual web addresses to the OpenDNS blocklist, this feature is next to useless. First, we found that adding a website address didn't actually block the website in many cases. Second, the lack of a bulk upload feature makes this useless. If you want to match your hosts file blocklist you have to add each entry one-by-one.

Conclusion

Although OpenDNS Home is the more advanced version of FamilyShield, it's actually an inferior solution since it's easier to disable and more complicated to set up. The additional features aren't good enough to make up for the reduction in reliability.

NextDNS

NextDNS  is one of the newer content filters that mainly caters to blocking Ad tracking and increasing privacy. However, they also block adult content and time-wasting websites. NextDNS is particularly interesting because they crowdsource their blocklists. All blocklists are sourced from GitHub repositories that contain curated blocklists. These blocklists are updated regularly, so it's a pretty good crowdsourced blocking solution.

Pros

• Costs only a few dollars per month.
• Supports IPv6 and hostnames
• Crowdsourced blocklists
• Roaming client for connecting a computer or smartphone to NextDNS on any internet connection (not just for at home use)

Cons

• Does not use machine learning for real-time blocking - it relies on crowdsourced lists entirely. It's more accurate than OpenDNS, but less accurate than all other content filters we review.
• No advanced circumvention techniques: the roaming client is easy to disable and doesn't account for the most common methods for getting around DNS Filtering.

Conclusion

Since NextDNS is relatively new, we expect it to improve significantly. We'd recommend it over OpenDNS, but it's one of the weaker Adult content filters.

CleanBrowsing

Cleanbrowsing  is one of the more popular home DNS filters specifically catering to blocking adult content.

Pros

• Costs only a few dollars per month (and also has a free tier).
• Supports IPv6 and hostnames, so router compatibility is good.
• Provides an app for configuring filtering on individual devices and there are some prevent uninstall features that you can enable.

Cons

• Security threat protection is not a focus, so these capabilities are lacking.
• It can noticeably slow down your internet connection depending on where you live. This is due to the limited number of servers in their network, so the roundtrip to resolve DNS queries is longer compared to services like Cloudflare.
  

Conclusion

Although it's not our top recommended filtering service, CleanBrowsing can be a good option for starting out with filtering content. The main issue is that it can slow down your internet connection depending on your location.

DNSFilter

There's a company that is smartly named "DNSFilter." DNSFilter is a market-leader in DNS filtering solutions, mostly focused on enterprise customers.

Pros

• Uses machine learning to classify content faster than services like NextDNS
  
• A good mix of security features and the ability to block adult content and related categories
• Supports invisible installation of their filter application so that it is harder to bypass
  
• This is a more technical concept, but you can use a hostname instead of an IP address to point your home router to the filter, which makes it easier to account for IP changes.

Cons

• DNSFilter provides a 14-day free trial, then it's $20/month for use on the home network and to  install roaming clients on your computer . If you want Android and iOS roaming clients, your cost goes up to $100/month
• Using DNSFilter on an iPhone requires you to set up a managed device. This process can take weeks and isn't an option for many people.
• Setting up DNSFilter in the most effective way is more difficult than any of the other DNS filtering solutions.
• Does not support IPv6.
• Internet access is completely blocked if filtering is not properly configured. This can be ideal for a corporation, but not so great if you are using it at home. Losing internet access and having to troubleshoot can be a huge headache.
  

Although the filtering capabilities are quite good, the cost and lack of support for iPhone is a major dealbreaker for most people. It can be a decent solution if you mostly use Android and care more about blocking porn on a router .

Final Verdict

Although there are many strong candidates for DNS Filtering, the ones that tend to work better for blocking porn are more focused on parental controls. However, DNS Filters that block porn in 2024 need to consider everyone in the household, not just kids. 

Furthermore, it's not enough to just block a generic Adult Content category. This problem requires more nuance, so empowering people to schedule usage to break bad habits is an important feature to consider. Additionally, categories and apps that aren't a problem for some people will be a problem for others. It's important that you have the freedom to customize in that level of detail.

As you can probably tell, I couldn't find an effective porn blocking DNS Filter that satisfied every requirement I had, which is why I had to build my own.