Portmaster

You view and limit network connections per program on Windows or Linux.

Developer Safing

Version 2.2.3 · Freemium · Windows · Linux

Looking for an alternative to Portmaster?Compare simplewall, TCPView.Compare alternatives

Portmaster provides insight into outgoing connections and provides rules to block traffic. You can review domains and connections and use privacy-oriented filter lists. This allows you to better see which apps are contacting external services.

The free local firewall features and the paid SPN network are different components. Installing Portmaster doesn't mean that all your traffic automatically runs through a paid privacy network. Choose which protection you want and check that your apps continue to work with the rules.

Which software suits you?

Compare Portmaster with alternatives

For control over outgoing traffic, insight per app is important. Compare how connections are shown, how to create rules and how DNS traffic is handled. A wrong line can block synchronization or updates; make sure you can easily reverse a change. In network research, the difference is whether you only want to see active connections or apply rules. Check if you can recognize local addresses, external addresses and the associated process. A process name alone does not yet tell whether a connection is undesirable.

Differences between Portmaster and simplewall, TCPView
Software	What can it do?	Platform and licence
PortmasterYou are viewing this app	You view network traffic by app and set rules and privacy filters. This combines insight into connections with possibilities to limit traffic.	Windows, LinuxFreemium
simplewallView this alternative	You manage allowed and blocked connections on Windows via the Windows Filtering Platform features. You control app rules yourself.	WindowsOpen source
TCPViewView this alternative	You are viewing active TCP and UDP connections to the Windows processes they use. The app is aimed at direct connection overview.	WindowsFreeware

Choose an alternative to explore its features, system requirements and download options.

Who is it for?

You want more insight into network traffic and are willing to keep track of rules and exceptions.

Getting started

Install Portmaster for your system and first view the connections of your normal apps. Then set targeted rules.

Privacy

Local filtering can limit unwanted connections. DNS settings and optional SPN functions determine which additional providers are involved.

Good to know

Support and integration vary by system. SPN and other additional functions have separate conditions.

Please note

Filter lists and strict rules can log in, disrupt payments or synchronize. Make targeted exceptions instead of allowing everything.

Advantages

Connection View by Program Rules by domain and by app Local basic features without SPN subscription

Things to consider

Can block legitimate traffic Rules for maintenance SPN is a separately paid offer

Download Portmaster

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Official download page

Provider’s website · safing.io

Download Portmaster

Version history

2.2.3 14 Aug 2026

Your network filter will continue to work better with faulty DNS packages and after a restart.

Portmaster 2.2.3 prevents too large DNS packages from disabling the internal DNS listener. Also mDNS, restoration of background tasks and initial restart have been improved. On Windows it has been corrected that removing Portmaster could overwrite other startup entries.

Report a new version

Our verdict

Portmaster is interesting if you want to see what connects behind the scenes and then do something with it. The combination of insight and filtering is strongest when you want to limit concrete unwanted connections. This gives you more grip than with only general privacy settings.

The program does require attention as soon as an app is no longer working properly. Then search for the blocked connection instead of disabling any security. For those who want to do that management, Portmaster can be useful. Do not expect complete anonymity of the free local firewall; it has a different purpose than the optional SPN network.