Paessler PRTG

Consistent, high-quality communication is yours

PRTG brings clarity and reliability to your Internet voice calls for free


  • Get to the root of your video and Internet call problems for improved performance
  • Analyze your VoIP traffic and intervene when load volumes increase
  • Identify security threats and ensure compliance by monitoring call data
  • Enjoy up to 100 PRTG sensors at no cost for free VoIP monitoring

Our users give top ratings for monitoring with Paessler PRTG



PRTG makes free VoIP monitoring easy

Custom alerts and data visualization make it easy to monitor, identify, and prevent quality of service issues.










Keep your call system up and running with free VoIP monitoring

Paessler PRTG’s free VoIP monitoring is the caretaker for your digital communications, quietly watching for potential issues with call quality and reliability. Know when to act before an issue arises.

Stay secure and compliant
in real time

VoIP (Voice over Internet Protocol) systems are vulnerable to cyber threats that can compromise the confidentiality of your communications. Eavesdropping, data theft, and service disruptions are all areas that need to be considered.

PRTG helps prevent unauthorized access, detect activities that may be malicious, and ensure your data security is up to regulatory standards.

Do more VoIP analysis with… more

Troubleshoot your VoIP with specialized sensors to monitor the various aspects of QoS, and then decide what to do with the other 95 free sensors.

PRTG comes with 100 free sensors you can use for as long as you want, as well as free reports and a notification system. Get the VoIP monitoring you need and a whole lot more.

Keep your fingers on the pulse of your network

Monitoring your VoIP helps your IT team improve performance and reduce problems often caused by network issues such as malfunctioning servers or bandwidth allocation.

PRTG provides comprehensive network monitoring so you can see the root cause of the issues and continually improve outcomes – all from a single pane of glass.



Customize your alert system

Get an immediate alert whenever something goes wrong with your VoIP. PRTG’s highly-rated alert system provides a general set of alerts and allows you to customize them for your own needs.

Receive notifications via email, SMS, and other channels to quickly address VoIP issues, identify the source of errors, and take action immediately.

Deep dive with in-depth reports

Comprehensive VoIP traffic analysis can help identify and diagnose network issues affecting your VoIP performance. PRTG’s continual monitoring allows you to analyze data patterns to pinpoint problems like network congestion.

Being able to see exactly where bottlenecks and trouble spots are allows your IT team to improve the network in targeted areas based on data.


Start VoIP monitoring for free with PRTG and see how it can make your network more reliable and your job easier.



IT experts agree: Paessler PRTG is a great solution for IT infrastructure monitoring


“All-around winning
network monitor”

logo it brief

“The real beauty of PRTG is the endless possibilities it offers”


“PRTG Network Monitor
is very hard to beat”








What free VoIP monitoring looks like in PRTG

Diagnose network issues by continuously monitoring the quality of your VoIP system. Show VoIP jitter and latency, as well as packet loss in real time and visualize data in graphic maps & dashboards to identify problems more easily. Gain the visibility you need to troubleshoot quality of service issues.


Easily find the source of the problem with our PRTG free VoIP monitoring solution

Real-time alerts and custom notifications make it easy to solve issues with call and video quality.



PRTG is compatible with all major vendors, products, and systems

vendors applications blue


4 reasons to choose our free VoIP monitoring tool

Intuitive, easy to use, and cost-effective

More than 500,000 users trust PRTG’s user-friendly interface. It’s easy to install, manage, and navigate, even if you have limited technical expertise. All your important data is available in a central visual dashboard, as well as on a variety of mobile devices.

Best of all, PRTG doesn’t need any special hardware or agents for QoS monitoring, so it’s cost-effective for any business size.

Preconfigured sensors to get you started

PRTG’s free VoIP monitoring has a convenient tool set of native sensors to help you quickly troubleshoot your VoIP. Use, for example, the QoS (Quality of Service) Round Trip sensor to measure your service and connection quality, reachability, percentage of packets and packet loss, or the jitter value of a series of pings with the Ping Jitter sensor. Systems with Cisco devices can take advantage of the Cisco IP SLA sensor.

Scale VoIP monitoring with your business

You can try the full, unlimited version of PRTG for 30 days free of charge. After this time, you’ll continue to get access to 100 sensors for as long as you like. PRTG is an industry-leading monitoring solution that is designed to grow with your needs. Start with free VoIP monitoring and all the free network monitoring benefits that come with PRTG, and upgrade when you’re ready.

Monitor your VoIP from wherever you are

You can have peace of mind in the office, in the car, at home, or on the beach. PRTG lets you remotely monitor your VoIP system, so quality and performance are maintained no matter where you are.

Access the central dashboard from your desktop or on our PRTG apps for iOS and Android, and be alerted of any IT infrastructure issue via push notification.


Your free VoIP monitor at a glance – even on the go

Set up PRTG in minutes and use it on almost any mobile device.


PRTG comes with all the features you need, plus more your IT infrastructure won't want to live without.



PRTG monitors these vendors and applications in one view!


vendors vm ware



Create innovative solutions with Paessler’s partners

Partnering with innovative vendors, Paessler unleashes synergies to create
new and additional benefits for joined customers.


With ScriptRunner, Paessler integrates a powerful event automation platform into PRTG Network Monitor.

Read more


Siemon and Paessler bring together intelligent building technology and advanced monitoring and make your vision of intelligent buildings and data centers become reality.

Read more


UVexplorer integrates tightly with PRTG to bring fast and accurate network discovery, detailed device inventory, and automatic network mapping to the PRTG platform.

Read more



“Excellent tool for detailed monitoring. Alarms and notifications work greatly. Equipment addition is straight forward and server initial setup is very easy. ...feel safe to purchase it if you intend to monitor a large networking landscape.”

Infrastructure and Operations Engineer in the Communications Industry, firm size 10B - 30B USD

Read the entire review at Gartner Peer Insights 


PRTG makes free VoIP monitoring easy

Custom alerts and data visualization make it easy to monitor, identify, and prevent monitor, identify, and prevent quality of service issues.


Free VoIP monitoring: FAQ


1. Why is VoIP monitoring important?

Quality, reliable business communications are crucial to stay in operation. VoIP monitoring performs several functions necessary to ensure business continuity:

  • Makes sure your Internet communications stay reliably high quality
  • Helps detect potential network performance issues before they happen
  • Provides network resource management to reduce downtimes and upgrade needs

2. What kind of issues does VoIP monitoring detect?

VoIP monitoring tools report on issues that impact your voice communications. Key metrics include latency, jitter, and packet loss, all of which can significantly affect call quality.

3. What is a voice packet?

In VoIP terminology, a “voice packet” is a unit of data that carries all the information about your voice. When you speak, your voice is turned into an encoded, compressed snippet of data and then broken down into smaller pieces that are easier to transmit. These pieces are called “packets”.

4. What is packet loss?

Packet loss means what it sounds like. Somehow, one or many packets of data have been lost in transmission. If you’ve ever been in a VoIP call that cuts in and out or a video call where someone freezes in the middle, you’ve experienced packet loss.

5. What causes packet loss?

Packet loss can be caused by several issues that VoIP monitoring detects. An overloaded network, for example, can cause congestion. Problem routers or switches can be an issue, as well as software bugs, firewalls, and weak network signals.


6. What is latency?

When you ask a question and wait for the other person to answer, the space in between is latency. In that space are a lot of “time” measurements:

  • How long the signal takes to travel from your computer to the other end of the call
  • How long it takes for all the packet’s bits to be received
  • How long it takes to process the packet
  • How long the packet has to wait on a busy network

If any of these areas have high latency, it will significantly affect the quality of your VoIP call.

7. What is jitter?

If latency is the time it takes to process a packet, jitter is how inconsistent the time on delivery is. Ideally, there’s no delay, meaning low jitter. Congested networks, inconsistent network quality, and improper queuing, among other network issues, can cause high jitter and quality of service issues.

8. What is the Mean Opinion Score?

The Mean Opinion Score, or MOS, is a metric that measures the quality of voice calls. The MOS is your VoIP report card. Individuals grade the quality of the call when it’s finished, and then those grades are averaged. The average score becomes the MOS.


9. What features should a VoIP monitoring tool include?

A comprehensive VoIP monitoring tool should provide the following:

  • advanced, real-time analytics
  • key metric monitoring, such as packet loss, jitter, latency, and MOS
  • real-time alerts
  • detailed reporting to easily identify recurring problems and trends
  • network traffic analysis
  • security monitoring
  • ability to easily integrate into network management systems

10. What is a sensor in PRTG?

In PRTG, “sensors” are the basic monitoring elements. One sensor usually monitors one measured value in your network, for example the traffic of a switch port, the CPU load of a server, or the free space on a disk drive.

On average, you need about 5-10 sensors per device or one sensor per switch port.


PRTG the multi-tool

PRTG: The multi-tool for sysadmins

Adapt PRTG individually and dynamically to your needs and rely on a strong API:

  • HTTP API: Access monitoring data and manipulate monitoring objects via HTTP requests
  • Custom sensors: Create your own PRTG sensors for customized monitoring
  • Custom notifications: Create your own notifications and send action triggers to external systems
  • REST Custom sensor: Monitor almost everything that provides data in XML or JSON format


More than just a monitoring tool:
Reasons our customers love PRTG



Still not convinced?


More than 500,000
sysadmins love PRTG

Paessler PRTG is used by companies of all sizes. Sysadmins love PRTG because it makes their job a whole lot easier.


Monitor your entire IT infrastructure

Bandwidth, servers, virtual environments, websites, VoIP services – PRTG keeps an eye on your entire network.


Try Paessler PRTG
for free

Everyone has different monitoring needs. That’s why we let you try PRTG for free.



Paessler PRTG 

Start VoIP monitoring for free with PRTG and see how it can make your business communications more reliable and your job easier.



Network Monitoring Software - Version (May 28th, 2024)


Download for Windows and cloud-based version PRTG Hosted Monitor available


English, German, Spanish, French, Portuguese, Dutch, Russian, Japanese, and Simplified Chinese


Up to 100 sensors for free (Price List)

Unified Monitoring

Network devices, bandwidth, servers, applications, virtual environments, remote systems, IoT, and more

Supported Vendors & Applications

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