Best Web Filtering Software: 11 Tools for Work and Schools

Web filtering used to mean a box in the server room that blocked a list of websites. Now people work from home, students carry devices between lessons, and threats arrive through links in messages as often as through browsing.

Modern filtering tools mostly work at the DNS level or in the cloud, so they protect a device wherever it connects. The eleven tools below are listed alphabetically and in no particular order, and every description comes from the vendor's own site, read this week. If DNS is a new term for you, start with my explainer on what DNS is.

Web filtering tools side by side

In the free plan column, Yes means the tool's own site names a free plan, a free version, a free edition or open-source code. Trial only means a time-limited trial. Not stated means the pages I read named neither, even where there's a button inviting you to try it.

Tool	Type	Good for	Free plan
Cisco Umbrella	DNS-layer security and web filtering	Blocking bad sites at the DNS layer	Trial only
Cloudflare Gateway	Secure web gateway	Teams already using Cloudflare	Not stated
Control D	DNS filtering service	Filtering on every operating system	Trial only
DNSFilter	DNS filtering and security	MSPs filtering many client networks	Trial only
Lightspeed Filter	Internet content filter for schools	US school districts with Chromebooks	Not stated
Netsweeper	Content filtering and digital safety	Schools, telcos and governments	Not stated
NextDNS	Cloud DNS firewall	Tech-savvy small offices	Not stated
SafeDNS	Cloud-based DNS filtering	Simple filtering for small organisations	Trial only
Securly	Filtering and monitoring for schools	UK schools following KCSIE	Not stated
Smoothwall	Digital safeguarding solutions	Safeguarding leads in UK education	Not stated
WebTitan	DNS filtering with threat protection	MSPs reselling web filtering	Not stated

Eleven web filtering tools to consider

Cisco Umbrella

Best for: Businesses that want malicious and unwanted websites blocked at the DNS layer before a connection is ever made.

Cloudflare Gateway

Best for: Organisations already on Cloudflare that want web filtering and secure internet access for staff wherever they work.

Control D

Best for: Small businesses and IT providers that want DNS filtering they can deploy in minutes on any operating system.

DNSFilter

Best for: Managed service providers and businesses that want DNS filtering on every device and network, managed from one place.

Lightspeed Filter

Best for: Schools and districts that want content filtering built for education, following students across school devices.

Netsweeper

Best for: Education providers and network operators that want large-scale content filtering with a focus on digital safety.

NextDNS

Best for: Small offices and technical users who want a cloud DNS firewall to block threats, ads and trackers across devices.

SafeDNS

Best for: Charities, schools and small organisations that want straightforward cloud DNS filtering they can try before committing.

Securly

Best for: UK schools that want filtering and monitoring designed around Keeping Children Safe in Education.

Smoothwall

Best for: Schools and colleges that want filtering and monitoring framed around safeguarding, from a long-standing UK education specialist.

WebTitan

Best for: Businesses and service providers that want DNS-based web filtering with AI threat protection from TitanHQ.

Schools need filtering and monitoring

The Department for Education says schools and colleges have a statutory responsibility to keep children safe online, and that governing bodies should make sure appropriate filtering and monitoring systems are in place. It explains that filtering is preventative, while monitoring doesn't block anything.

For a school, that means a filter alone isn't the full job. You also need to see what's happening and act on it, which is why several tools here sell filtering and monitoring together, built around safeguarding.

DNS filtering or a full secure web gateway?

DNS filtering blocks a site before a connection is made, which is light, quick and easy to roll out to every device. A secure web gateway inspects more of the traffic itself, which gives finer control in return for more set-up.

Most small businesses get what they need from DNS filtering. Larger organisations with strict data rules often add a gateway on top. If you're not sure which you need, it's easy to start with DNS and add more later, but it's much harder to roll a heavy gateway back once it's in.

Questions to ask a filtering vendor

1. Does filtering follow laptops and phones off site?
2. Which categories can we block, and can we make exceptions?
3. How do you handle encrypted sites?
4. What reports do managers or safeguarding leads get?
5. Can different groups have different rules?
6. How quickly are new malicious sites added to block lists?

Signs your web filtering needs a rethink

• Filtering stops at the office door. Remote devices browse unprotected.
• Staff complain about blocked work sites. Rules are too blunt.
• Nobody reads the reports. Alerts pile up unseen.
• Safeguarding leads can't see activity. Monitoring is missing.

Do you make web filtering software? Tool makers can ask to be considered for a featured place on this list.

My plain advice on choosing web filtering software

Decide what you're trying to stop before you compare tools. Blocking malware and phishing is very different from blocking social media at work, and blocking too much just teaches people to find workarounds.

For schools, involve your safeguarding lead from day one, because reports and alerts are what they'll live with. And whatever you choose, explain the rules to staff or students rather than hiding them. For a wider view on AI in schools and workplaces, see my take on whether schools and businesses should allow AI tools.

Frequently asked questions

What is web filtering software?

It's software that controls which websites people can reach, blocking harmful, malicious or unwanted content on a network or device.

What is DNS filtering?

DNS filtering checks the website address a device is trying to reach and blocks it before a connection is made if it's on a blocked list.

Do schools have to use web filtering?

In England, the Department for Education expects schools and colleges to have appropriate filtering and monitoring systems in place as part of their safeguarding duties.

Does web filtering work on remote laptops?

Many modern tools install a small agent or use cloud DNS so filtering works wherever the device connects.

Can web filtering stop phishing?

It helps by blocking known malicious sites, but it should sit alongside training, email security and other protections.

Will web filtering slow down the internet?

DNS filtering adds very little delay. Heavier inspection tools can add more, which is worth testing during a trial.