Bandwidth Monitoring Tools

What is bandwidth monitoring and why is it important?

A bandwidth monitor tool provides real-time insights into usage across your network so you can proactively manage any bandwidth limits but most importantly identify bandwidth hogs on your network which could point to other issues such as a network intrusion.

Here’s our list of the best bandwidth monitoring tools:

  1. SolarWinds Real-Time Bandwidth Monitor EDITOR’S CHOICE A free bundle of tools that uses NetFlow, J-Flow, and sFlow to record traffic patterns and capture packets. It is 100% free to download.
  2. Paessler PRTG Network Monitor (FREE TRIAL) The PRTG tool contains a large number of sensors, among which are NetFlow and sFlow monitors.
  3. SoftPerfect NetWorx Free for 30 days, this tool for Windows, Mac OS, and Linux would be perfect for monitoring small networks.
  4. ManageEngine Bandwidth Monitor Part of a suite of infrastructure monitoring tools, this utility uses NetFlow messaging to examine network traffic.
  5. ntopng With a free community edition, this open-source network monitor uses nProbe to gather traffic flow information.
  6. SolarWinds Real-Time NetFlow Analyzer (FREE TOOL) An alternative free bandwidth monitor from SolarWinds. Runs on Windows.
  7. Progress WhatsUp Gold A network monitoring tool that installs on Windows and can be extended by a specialized Network Traffic Analysis module.

Why monitor internet bandwidth?

If you run a WAN with a lot of interaction between sites, if you integrate Cloud services into your IT infrastructure, or if your main business outlet is your website, your bandwidth monitoring needs to cover internet performance as well as network bandwidth utilization.

You no doubt have a service plan with an internet provider to connect your business together across the world and to communicate with suppliers and customers. You may have chosen a plan that does not provide you enough bandwidth. You will only discover that situation when you monitor bandwidth consumption on your internet connections.

Related post: The difference between Throughput and Bandwidth

Why use a network traffic monitor tool?

Your ISP promises to provide you with a reliable pipe to the Internet of a certain volume; your chosen network hardware install is designed to provide a particular level of service within your facility. Are you getting your expected bandwidth and availability, or is something failing to deliver? Is unexpected traffic consuming the bandwidth that you are getting?

Tools that monitor network traffic and bandwidth such as data usage meters can leverage various technologies. A host can observe all the data packets passing by a particular network interface (that is, packet capture). Most managed network devices – and hosts – support SNMP, and so they can be queried to get performance statistics.

Bandwidth monitoring focuses on the available capacity of network equipment and the amount of that capacity that is occupied by traffic. You can extend that visibility further by getting a breakdown of traffic volumes by application or by source and destination to spot where the real bandwidth hoggers are.

Network traffic statistics

You need to watch the bandwidth consumption of each link in your network, not just the overall bandwidth availability. One link can get congested, while others retain spare capacity. Adding on extra bandwidth to alleviate overloading on one link can cause extra throughput to get through and overload other links. That congested link may be hiding the under-provision of bandwidth in other areas of the network.

If your network devices support a traffic monitoring protocol like NetFlow or sFlow, they can publish traffic data to your monitoring tool. For more on these technologies, see Intro to traffic analysis in The best free NetFlow analyzers and collectors for Windows, and NetFlow vs sFlow: What’s the difference and which is better?

Network bandwidth monitoring tools

Which network bandwidth monitoring tools are right for you? There are several considerations when performing a network monitoring tools comparison. One factor is what monitoring technologies your installed hardware supports (eg, do they support SNMP? NetFlow? sFlow?). One is the size and complexity of your network; a simple tool that’s a great fit for a small office is completely inadequate for a large sophisticated network. Here we’ll look at the most popular and feature-rich free bandwidth monitoring software that can give you real-time data on your network and internet connection bandwidth utilization.

Monitoring tools that enable you to perform a network bandwidth test on-demand provide analytical functions. Troubleshooting bandwidth problems is impossible without the ability to collect and store network traffic.

Bandwidth monitoring requirements

You need a tool that can monitor your network for you while you are busy with other tasks. To get that level of service from your bandwidth monitor, make sure you choose a tool that is able to monitor router traffic levels approaching your full bandwidth availability and send you alerts. Reports that can be scheduled at all hours of the day will also help you keep watch on your bandwidth utilization 24/7.

Analytical features in tools help you plan your capacity requirements both to meet current demand, to account for trend traffic increases, and to provision for extra services when demanded.

If your chosen bandwidth tool can save collected traffic to a file, open files, and traffic data into a viewer, then you can begin to observe traffic patterns over time. Viewers that include filtering, sorting, and tagging capabilities will allow you to identify the sources of bandwidth capacity problems. Analytical tools that have sophisticated graphical representations for network data and comprehensive reporting formats will enable you to communicate problems and solutions to stakeholders in your organization and arrive at collaborative decisions.

The best bandwidth monitoring software

We have taken all of the above requirements into account and compiled recommendations on the software that you should consider when you are in the market for  bandwidth monitoring software. There are many great monitors available at the moment, but you won’t have enough time to check all of them out. So, we wrote this guide in order to cut down the time you have to spend investigating new software for your enterprise.

What should you look for in free bandwidth monitoring tools? 

We reviewed the available free bandwidth monitoring software and analyzed the options based on the following criteria:

  • The capability to use traffic sampling protocols, such as NetFlow
  • Time-series maps showing traffic volumes
  • Traffic monitoring per link and point-to-point
  • Alerts for devices reaching full capacity
  • Traffic shaping measures
  • Traffic analysis tools to aid capacity planning
  • An option to upgrade to a comprehensive paid system

1. SolarWinds Real-Time Bandwidth Monitor – FREE BUNDLE DOWNLOAD

SolarWinds makes a suite of products providing comprehensive support for network monitoring and management. Their Real-Time NetFlow Traffic Analyzer provides useful data about bandwidth for devices that support NetFlow; we discussed this tool in an earlier post on the best free NetFlow analyzers and collectors. Here we’ll focus on another free tool from SolarWinds, the Real-Time Bandwidth Monitor.

The SolarWinds Real-Time Bandwidth Monitor runs on Windows. It uses SNMP to poll multiple network interfaces in real-time for their traffic statistics and visually displays the status of a chosen interface graphically.

SolarWinds RTBM : List of discovered interfaces that can be monitored

Figure 1: List of discovered interfaces that can be monitored

Once you’ve provided the IP address and SNMP parameters for the device or host, the Real-Time Bandwidth Monitor lists the interfaces there and basic data about them.

SolarWinds RTBM: Graphical display of an interface's usage

Figure 2: Graphical display of an interface’s usage

Selecting one of the interfaces provides you with a graphical display of bandwidth usage on that interface.

SolarWinds RTBM: Setting thresholds for alerting on an interface's usage

Figure 3: Setting thresholds for alerting on an interface’s usage

You can set per-interface thresholds so that the graph displays an alert when usage exceeds your chosen limits.

The Real-Time Bandwidth Monitor is a great way to see what’s going on at particular interfaces, particularly for devices that do not support NetFlow (or sFlow). The SolarWinds Real-Time Netflow Traffic Analyzer can roll up traffic by conversation, application, domain, endpoint, and protocol; the Bandwidth Monitor works from more basic metrics, so it can’t do that. But when you have devices that don’t support the traffic flow monitoring protocols, the Real-Time Bandwidth Monitor is an essential tool.


  • 100% free
  • Simple, accurate real-time monitor with no unnecessary features or bloat
  • Easy graphing can help visualize traffic flow with time and events
  • Threshold-based alerts are flexible for networks both large and small
  • Comes bundled with SolarWinds Network Analyzer


  • Lacks some of the advanced reporting and alerting features found in paid software

TWO FREE TOOLS: Get both free tools from SolarWinds in the Bandwidth Monitoring Bundle.

You can also get both those free tools from SolarWinds in the Network Analyzer & Bandwidth Monitoring Bundle.

Another option for bandwidth monitoring that is offered by SolarWinds is the ipMonitor. This is not a free tool, but you can try it on a 14-day free trial. This is a specialist tool that monitors network usage, servers, and applications. It keeps you aware of all network performance metrics, including uptime availability, internet service quality, and network capacity. This monitor works on real-time network data including alerts and reporting functions, and it will help you head off capacity-related system failure.

If you decide to move up to a for-cost tool that can grow with your business up to enterprise scope, Network Bandwidth Analyzer Pack includes Network Performance Monitor and NetFlow Traffic Analyzer; for more on those tools see SolarWinds NetFlow Traffic Analyzer review.

Key Features:

  • Uses NetFlow, J-Flow, and sFlow
  • Shows live data flows
  • Stores traffic metrics for analysis
  • Identifies bottlenecks


The Real-Time Bandwidth Monitor is a powerful tool which not only monitors and graphs multiple network interfaces in real-time but you can also set up per-interface thresholds and alerts, particularly for devices that don’t support NetFlow. Bundled with a free network analyzer, you can see traffic by conversation, app, domain, and endpoint. It’s also 100% free.

Start 30-day Free Trial:

OS: Windows

2. Paessler PRTG Network Monitor (FREE TRIAL)

The Paessler PRTG Network Monitor is a “batteries included” solution that monitors bandwidth utilization, the health of devices on your network, and more. The free version is limited to 100 sensors after the first month; since a sensor is an individual data stream, each device will typically require several sensors.

The PRTG Network Monitor runs on Windows. It uses SNMP, WMI, NetFlow, sFlow, and packet sniffing. Setting up the tool is a bit complex but a setup wizard and how-to video are provided.

PRTG Network Monitor: Viewing top talkers, connections, protocols, and other utilization

Figure 11: Viewing top talkers, connections, protocols, and other utilization


  • Free trial that converts to a limited freeware version after expiration
  • Uses multiple protocols for monitoring allowing for a wide variety of uses and monitoring integrations
  • Supports custom sensors built for in house applications
  • Great option for companies looking for other monitoring solutions in the PRTG ecosystem


  • Takes time to get used to the feature-rich interface

The free version of PRTG Network Monitor provides a well-stocked toolbox for monitoring a small network, download the free trial here. For more details, see The best free NetFlow analyzers and collectors for Windows.

Key Features:

  • Uses NetFlow and sFlow
  • Packet capture function
  • Live traffic flow graphics
  • Identifies overloaded links
Paessler PRTG Network Monitor Download 30-day FREE Trial at

3. SoftPerfect NetWorx

Many network monitoring tool suites assume you’re administering a large and complex network, and so provide a sophisticated array of capabilities. But in the category of bandwidth monitoring, there are many tools that go in the other direction, monitoring the bandwidth of a single PC. That’s likely too minimalistic for you, but if you have a small office, and only need to monitor one (or a few) PCs and a single router, then SoftPerfect NetWorx may be the straightforward tool you need.

NetWorx is a clean tool that will monitor the bandwidth usage on one or more PCs, or a single Mac or Linux machine; and it can also monitor bandwidth on your router to the Internet via SNMP. NetWorx is now a licensed tool, so it’s only free for 30 days, after which you must spring for a (fairly cheap) license.

Key Features:

  • Monitors a small network or a single PC
  • Bandwidth, speed and usage reports

SoftPerfect NetWorx: Monitoring via SNMP with NetWorx

Figure 7: Monitoring via SNMP with NetWorx

Besides graphing bandwidth, NetWorx provides several tools like a speed meter and a per-user usage report.


  • Minimalistic design is good for non-technical users
  • Works for both Mac and Linux machines
  • Affordable for any size network


  • Barebones interface feels outdated
  • Designed for smaller networks, not enterprise-friendly
  • Limited charting options and reporting

4. ManageEngine Bandwidth Monitoring tool

ManageEngine produces a full network management suite and offers free versions of some of their tools. In our article on the best free NetFlow analyzers and collectors for Windows, we looked at the ManageEngine NetFlow Analyzer which provides real-time visibility into network bandwidth and traffic patterns, when you have devices that support NetFlow. The NetFlow Analyzer displays traffic by applications, conversations, protocols, etc; it can alert you to problems and has a range of report-generation options. Here we will focus on the Bandwidth Monitoring tool that is part of the free edition of ManageEngine OpManager.

The Bandwidth Monitoring tool leverages SNMP. It runs on Windows or Linux. The free edition supports monitoring 10 devices and their interfaces.

ManageEngine OpManager: Devices and their interfaces, and alerts

Figure 8: Devices and their interfaces, and alerts

Setting up the OpManager is a multi-step process but not overly complex. Once you provide the subnet and SNMP parameters, OpManager will scan your subnets and discover your devices. Then, from the inventory tab, you can check the status of devices’ interfaces. You can view graphs and tables of network usage, speed, and bandwidth, as well as device hardware metrics, either rolled up at the device level or drilling down to a particular interface.

ManageEngine OpManager: Roll-up for an interface

Figure 9: Roll-up for an interface

ManageEngine OpManager: Utilization graphs for an interface

Figure 10: Utilization graphs for an interface

At the interface level, you can generate reports showing bandwidth from the past 12 hours up to the past month. You can also set thresholds to receive automated alert email or SMS messages. By monitoring the gateway to your ISP, you can check your internet traffic usage and how much bandwidth you actually receive.

Key Features:

  • Uses NetFlow
  • Free version

The Bandwidth Monitoring tool, combined with the other features of the free version of ManageEngine OpManager, provides you with a well-rounded suite of capabilities for monitoring 10 or fewer devices on a small network.


  • Features a host of additional network management tools to compliment bandwidth monitoring
  • Offers a clean interface that combines visualizations with a trailing log of real-time reports
  • Makes charting traffic patterns and high usage times easy with flexible visualization and alerting tools


  • Inventory management feature could be reworked to be easier to filter and use

5. ntopng

ntopng is an open-source web-based traffic analysis tool. The community version of ntopng is free; the professional (small business) and enterprise versions require buying a license. All versions do packet capture; the enterprise version also uses SNMP. To receive flow data ntopng depends on nProbe; a fully-functioning version of nProbe requires a paid license. Licenses are free to educational and nonprofit organizations.

ntopng: Viewing flows

Figure 12: Viewing flows

ntopng’s web-based user interface rolls up data into traffic (eg, top talkers), flows, hosts, devices, and interfaces.

ntopng: Viewing protocols
ntopng: Viewing protocols

Key Features:

  • Packet capture
  • Traffic flow statistics
  • Community Edition is free to use

ntopng is a richly-featured open-source traffic and bandwidth monitoring tool.


  • Open-source project with full transparency
  • Free version available alongside the enterprise version
  • Special licensing options for nonprofits and educational institutions


  • Not the best option for larger multi-site networks
  • Packet capture features are a bit limited
  • User interface is easy to use, but could be improved upon

6. SolarWinds Real-Time NetFlow Analyzer (FREE TOOL)

SolarWinds Teal-time NetFlow Traffic Analyzer

The Real-Time NetFlow Analyzer will track traffic on the NetFlow interface of any given device on your network. The tool first traces all of your devices and lists them in a left-hand menu panel in the interface. You can switch between devices just by selecting a different IP address in the list.

The main panel of the screen shows live traffic and distinguishes the applications sourcing each traffic flow with different colors. With this display, you can see all of the applications operating on the network simultaneously. That segmentation of traffic can also be switched to show the endpoints, domain or protocol that generates the traffic instead of the applications. It can also compress the display to identify each active exchange, or conversation, being carried out on the network.

The tool is very lightweight and doesn’t take up much room on your computer. The beauty of the layout is that you don’t have to switch between screens because everything you need is on the home screen.


  • Open-source project with full transparency
  • Free version available alongside the enterprise version
  • Special licensing options for nonprofits and educational institutions


  • Graphing charts are a bit bare-bones

The tool runs on Windows and it is only intended for quick checks. It doesn’t support long-term traffic analysis because it is only able to store backs on a 60-minute timeframe. The Real-Time NetFlow Analyzer is provided by SolarWinds for download as a 100% free tool.

Key Features:

  • Uses NetFlow
  • Visual representations of traffic data
  • Free to use

SolarWinds Real-Time NetFlow Analyzer Download 100% FREE Tool

7. Progress WhatsUp Gold

WhatsUp Gold is a well-known network usage monitoring tool from Progress (formerly IPSwitch) that’s feature-rich yet straightforward. It’s available in both a free starter edition and a 30-day trial to evaluate the paid one.

WhatsUp monitors network traffic, servers, virtual servers, cloud services, and applications. The free version is a free five-point license for monitoring up to five resources (eg, five servers).

WhatsUp must be installed on Windows. Setup is simple and uses auto-discovery. The user interface provides multiple views with an interactive network map and the ability to drill down to investigate issues.

WhatsUp Gold list view lists discovered devices.
WhatsUp Gold list view lists discovered devices.

Traffic analysis facilities work with a wide range of flow-enabled devices, including NetFlow, sFlow, NetFlow-Lite, IPFIX, and J-Flow.

WhatsUp Gold's traffic analysis dashboard shows traffic status.
WhatsUp Gold’s traffic analysis dashboard shows traffic status.

Dashboards are customizable. WhatsUp provides many canned reports, including reports for bandwidth and utilization; you can design customized reports, too.

WhatsUp Gold's top 10 view shows the "top 10" devices with various statistics
Top 10 view shows the “top 10” devices with various statistics

You can configure alerts to notify you when senders or receivers exceed bandwidth thresholds when interfaces exceed utilization thresholds, etc. There are multiple possible methods for notification, including email and SMS. Triggered actions give the ability to execute actions automatically as responses to alerts.

Key Features:

  • Network performance monitor
  • Traffic analysis add-on

The free edition of WhatsUp Gold is a straightforward and fully featured tool for monitoring and managing a small shop. Graduating to the for-cost version lets you move up to covering large networks.


  • Great interface
  • Supports a wide range of flow enabled devices
  • Can support both virtual and physical hardware
  • Balances user experience with monitoring features quite well


  • Only available for Windows operating systems
  • Free version can only monitor up to five resources

Choosing bandwidth monitoring tools

Several good free options are available to monitor the bandwidth of your network. Picking the appropriate one will depend on your installed network hardware, the size and sophistication of your network, and how you expect it to grow.

Network Bandwidth Monitoring FAQs

How to analyze network traffic remotely?

Many network monitoring tools are able to cover WANs, allowing one central network management team to monitor the networks at many sites. Cloud-based network monitoring tools all operate a remote monitoring system. In order to get around network security, these remote monitoring tools usually require an agent service to be installed on the remote network.

How can I view the bandwidth of my critical applications?

A typical network traffic monitor is able to identify traffic by application. This is possible because specific applications communicate on specific ports. The source and destination port numbers are always written in the packet headers that carry network traffic. If you don’t have a traffic monitor but use a packet sniffer, you can identify each application’s traffic by de-referencing the port numbers in the packets that you capture.

What is the best way to identify traffic flow on an existing network?

Networks are made up of a series of links. In order to get a useful overview of the entire network, it is necessary to examine traffic flows on each link. This can be done by measuring the traffic throughput on each router per destination. Creating your own map of the network and identifying traffic throughput on each link is complicated, so it is better to perform this task with a specialized traffic monitoring tool.