So Sniffnet is worth checking out. It’s a free, open-source network traffic monitor that puts that invisible data flow right on your screen. Built in Rust with a native GUI — Windows, macOS, and Linux all get proper installers. Over 40,000 GitHub stars with v1.5.0 out in April 2026. This is not some abandoned side project.

Bottom line up front: If you want visibility into what your machine sends and receives — which apps, which servers, how much data — without paying for a commercial tool or climbing Wireshark’s learning curve, Sniffnet is a great free option.

What Sniffnet Does

Pick a network adapter, and the app starts showing every live connection: source IP, destination IP, protocol, data volume, and the program responsible. Here’s how it stacks up against the other well-known options:

That 6,000+ protocol detection number sets it apart. That said, most packet analyzers either have a smaller database or require paid subscriptions. Plus the detection runs entirely locally — nothing leaves your machine.

Yet the geographical mapping is another standout. Each connection gets plotted on a world map with the remote host’s estimated location. Still not sure if that server in a foreign country is legitimate? The map makes it obvious. This is especially useful for spotting suspicious outbound connections — something we cover a lot in our privacy tool tests.

Now program-level filtering landed in v1.5.0 and it changes things for a tool like this. Instead of guessing which process generated a packet, you see the actual program name — Chrome, Steam, OneDrive, System, your VPN client. Makes troubleshooting a lot faster.

Hands-On: Sniffnet on Windows

We downloaded the Windows x64 MSI installer and had Sniffnet running in under two minutes. The GUI is clean — dark-themed dashboard with inbound/outbound traffic plotted as a real-time chart. Selecting our Wi-Fi adapter started populating connection data right away.

Within 30 seconds we could see which remote IPs our machine was talking to, the domain names and ASN for each host, data volume per connection, and the program responsible for each one. One thing that caught our attention: a constant trickle of traffic to a Microsoft-owned subnet, likely Windows telemetry. Still not alarming, but you just don’t see this without a dedicated network monitor.

Though the initial run required admin privileges — expected for any tool that captures raw adapter traffic — the whole install was straightforward. No dependency hunting, no command-line config. Other network tools like Blokada take a different approach by working at the DNS level, but Sniffnet gives you the full picture.

Sniffnet Limitations

Sniffnet is not a packet-level debugger. If you need hex dumps of individual packets or TCP handshake analysis, Wireshark is still the right call. Sniffnet works at the connection level — summaries and metadata, not raw payloads.

Also worth noting: the Iced rendering engine can glitch on older GPUs. The project documents a simple workaround — set ICED_BACKEND=tiny-skia — which fixes it by switching to CPU rendering. Never needed it on our test device, but good that the fix exists.

Sniffnet Verdict

This Sniffnet review started with a simple question: can a free, open-source internet monitoring tool actually deliver useful data without a headache? The answer is yes.

Sniffnet fills a real gap. It’s more accessible than Wireshark, more polished than most CLI alternatives, and completely free. So for privacy-minded users who want to see what their computer does when they’re not looking — without a major time investment — it’s a solid choice.

If Sniffnet shows you what your machine sends, the next question is — who else can see it? Your ISP, for one. Pairing network visibility with a VPN gives you the full privacy picture: Sniffnet for monitoring, and a service like NordVPN (our top-rated VPN for privacy in 2026) (affiliate link) to encrypt that traffic end-to-end. Together they cover both sides of the same coin.