Best Free Packet Analyzers of 2025

Paessler PRTG is an all-inclusive monitoring solution with an intuitive, user-friendly interface powered by a cutting-edge monitoring engine. It optimizes connections and workloads, reduces operational costs, and prevents outages. It also saves time and controls service level agreements (SLAs). This solution includes specialized monitoring features such as flexible alerting, cluster failover, distributed monitoring, maps, dashboards, and in-depth reporting.

Utilize Telerik Fiddler HTTP(S) proxy to capture all internet traffic between your computer and external sites, allowing you to analyze that traffic, set breakpoints, and manipulate both requests and responses. Fiddler Everywhere serves as a versatile web debugging proxy compatible with macOS, Windows, and Linux platforms. You can capture, inspect, and monitor all HTTP(S) communication, facilitating the mocking of requests and troubleshooting of network problems. This tool is applicable to any browser or application, enabling you to debug traffic across macOS, Windows, Linux, and mobile devices running iOS or Android. It guarantees that the necessary cookies, headers, and cache settings are properly exchanged between client and server. Supporting diverse frameworks such as .NET, Java, and Ruby, Fiddler Everywhere empowers you to mock or alter requests and responses on any website efficiently. This straightforward approach allows for testing website functionality without the need for code alterations. By employing Fiddler Everywhere, you can effectively log and analyze all HTTP/S traffic between your system and the wider internet, streamlining your debugging process.

Tcpdump serves as a robust command-line tool for analyzing network packets, enabling users to view the details of packets sent or received over the network their computer is connected to. Compatible with a variety of Unix-like operating systems such as Linux, Solaris, FreeBSD, NetBSD, OpenBSD, and macOS, it leverages the libpcap library for capturing network traffic effectively. This utility can process packets either directly from a network interface card or from a previously recorded packet file, and it offers the flexibility to direct output to either standard output or a file. Users have the option to apply BPF-based filters to manage the volume of packets being analyzed, making it particularly useful in environments experiencing heavy network traffic. Tcpdump is distributed as free software under the BSD license, which promotes accessibility. Moreover, it is often included as a native package or port in numerous operating systems, making updates and ongoing maintenance straightforward for users. This ease of use contributes to its popularity among network administrators and analysts alike.

Arkime is a comprehensive open-source solution for large-scale packet capturing, indexing, and data management, aimed at enhancing the current security framework by preserving and organizing network traffic in the widely-used PCAP format. This system enables complete visibility into network activities, which is crucial for the rapid detection and rectification of security-related and network problems. Security personnel are equipped with vital visibility data that aids in the prompt response to incidents, allowing them to uncover the entire scope of any attacks. With its architecture designed for deployment across numerous clustered configurations, Arkime can effortlessly scale to handle traffic volumes of hundreds of gigabits per second. This capability empowers security analysts to effectively respond to, recreate, examine, and verify information regarding potential threats present in the network, facilitating timely and accurate countermeasures. Furthermore, as an open-source platform, Arkime not only offers users the advantages of transparency and economic efficiency but also promotes flexibility and receives robust community support, making it a valuable tool for any organization. Overall, Arkime stands out as an essential asset for organizations aiming to bolster their cybersecurity posture.

NetworkMiner, an open-source tool for network forensics, extracts artifacts like files, images, emails and passwords, from captured network traffic stored in PCAP files. It can also capture real-time network traffic by sniffing the network interface. The analyzed network traffic contains detailed information about each IP. This can be used to discover passive assets and get a better overview of communicating devices. NetworkMiner was designed to run primarily on Windows, but it can also be used with Linux. Since its 2007 release, it has become a favorite tool among incident response teams, law enforcement agencies and companies and organizations around the world.

Sniffnet is a network monitoring application crafted to assist users in effortlessly tracking their Internet traffic. It not only collects statistics but also delves into detailed network activities, offering extensive monitoring capabilities. The tool prioritizes user-friendliness, making it more accessible than many traditional network analyzers. Available as a completely free and open-source solution, Sniffnet is dual-licensed under MIT or Apache-2.0, with its full source code hosted on GitHub. Built entirely with Rust, this modern programming language enhances the software's efficiency and reliability while prioritizing performance and security. Among its standout features are the ability to choose a network adapter for analysis, implement filters on monitored traffic, observe overall statistics and live charts of Internet activity, export detailed capture reports in PCAP format, and identify over 6,000 upper-layer services, protocols, trojans, and worms. Additionally, it allows users to uncover domain names and ASNs of hosts, as well as trace connections within the local network, making it a versatile tool for network oversight.

EtherApe is a network monitoring tool for Unix systems that visually represents network traffic, inspired by Etherman, with hosts and connections dynamically changing size based on the amount of traffic and utilizing color coding for different protocols. It accommodates a variety of devices, such as FDDI, ISDN, PPP, SLIP, and WLAN, and supports multiple encapsulation methods. Users have the option to filter the traffic they see and can capture data in real-time or extract it from a file. Additionally, statistics for each node can be exported for further examination. The software features modes for link layer, IP, and TCP, enabling users to concentrate on particular levels of the protocol stack. Each node and link is displayed with comprehensive details, including a breakdown of protocols and traffic metrics. Released under the GNU General Public License, EtherApe is open source. A unique aspect of the interface allows a single node to be focused on while multiple selected nodes can be organized in a circular arrangement, complemented by an alternative display mode that aligns nodes in vertical columns. This versatility makes EtherApe a powerful tool for network analysis and visualization.

WinDump serves as the Windows adaptation of tcpdump, a powerful command line network analysis tool originally designed for UNIX systems. It is entirely compatible with tcpdump, allowing users to monitor, troubleshoot, and save network traffic to disk based on a variety of intricate rules. This tool can be executed on various Windows operating systems including 95, 98, ME, NT, 2000, XP, 2003, and Vista. Utilizing the WinPcap library and drivers, which are available for free from the WinPcap website, WinDump captures network traffic effectively. WinDump also facilitates wireless capture and troubleshooting for 802.11b/g networks when paired with the Riverbed AirPcap adapter. It is distributed at no cost under a BSD-style license and has the ability to utilize the interfaces made available by WinPcap. Additionally, WinDump can operate across all operating systems that are compatible with WinPcap, marking its role as a direct port of tcpdump. Users can initiate multiple sessions either on the same network adapter or across different adapters; while doing so may increase CPU usage, there are no significant disadvantages to running multiple instances simultaneously. This flexibility makes WinDump a valuable tool for network administrators and engineers alike.

Wireshark stands as the leading and most widely utilized network protocol analyzer in the world. This tool allows users to observe the intricate details of their network activity and has become the standard reference point for various sectors, including commercial enterprises, non-profit organizations, government bodies, and academic institutions. The continued advancement of Wireshark is fueled by the voluntary efforts of networking specialists from around the world, originating from a project initiated by Gerald Combs in 1998. As a network protocol analyzer, Wireshark enables users to capture and explore the traffic traversing a computer network interactively. Known for its extensive and powerful capabilities, it is the most favored tool of its type globally. It operates seamlessly across a range of platforms, including Windows, macOS, Linux, and UNIX. Regularly employed by network professionals, security analysts, developers, and educators worldwide, it is accessible without cost as an open-source application and is distributed under the GNU General Public License version 2. Additionally, its community-driven development model ensures that it remains up-to-date with the latest networking technologies and trends.