Ettercap
open-source
Open-source suite for man-in-the-middle attacks on LAN with sniffing, content filtering, and protocol dissection.
Open source network sniffers software to evaluate in 2026
Open source network sniffers software gives teams full code access, no per-user licensing, and the freedom to self-host, but operational cost replaces license cost. These are the open source options in this category, followed by the full list for comparison.
4 of 7 products in this category match the open source filter and are highlighted below.
Back to all Network Sniffers tools, or browse the full software directory. You can also run head-to-head comparisons or read about our review methodology.
For background on scoring, see how rankings work. Our editorial articles add deeper analysis, the glossary clarifies vendor terminology, and our calculators help estimate ROI before the shortlist narrows further.
Open source options
mitmproxy
open-source
Open-source interactive HTTPS proxy for intercepting, inspecting, and modifying network traffic.
tcpdump
open-source
Command-line packet analyzer for capturing and filtering network traffic on Unix-like systems.
Wireshark
open-source
Open-source network protocol analyzer for deep packet inspection, live capture, and offline analysis.
Other network sniffers tools
The rest of the network sniffers software category, listed because the open source filter above did not select them. Worth reading when the highlighted options do not fit.
Charles Proxy
one-time
HTTP proxy and monitor for viewing all HTTP and SSL traffic between a machine and the internet.
Fiddler
freemium
Web debugging proxy for capturing and inspecting HTTP/HTTPS traffic between client and server.
NetworkMiner
freemium
Network forensic analysis tool for extracting files, images, and credentials from captured traffic.
Common questions about open source network sniffers software
Is open source network sniffers software really free?
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The license is free, but hosting, maintenance, patching, and upgrades replace the vendor's license fee. Teams without dedicated ops resources often spend more on self-managed open source than on a managed commercial alternative.
When should I choose open source over commercial network sniffers software?
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Open source is strongest when you need full code control, on-premises deployment for compliance, or want to avoid vendor lock-in. It is weaker when your team lacks the ops capacity to maintain, patch, and scale the deployment.
What should I check before deploying open source network sniffers software?
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Check community activity (commits, issues, and releases in the last six months), commercial support options, documentation quality, and the total operational burden against a managed alternative. A dormant project with no commercial backing is a risk.