Today we’re kicking off the public beta for a new speed test that we plan to make available as open source software, so others can use it to create their own speed test, see how it works, or improve the code. Starting today, any Xfinity Internet customer can try out the new tool and provide feedback at

As with any open source project, we’re looking forward to other folks in the technical community improving the code, and adapting it for their own use. To move that process forward, we’ll be working with Princeton University to host a speed test hackathon in November, bringing together contributors from a range of institutions and organizations. We plan to make the code available on our GitHub page at the conclusion of the beta or just before the hackathon, whichever comes first.

Speed tests are invaluable. They help us confirm that we’re delivering fast Internet speeds and can help customers diagnose and detect issues that may be impacting performance such as Wi-Fi access point placement.

Like many ISPs, we offer a third-party-powered speed test tool. That tool performs exceptionally well, and millions of people use it regularly.

For this speed test, however, we are testing a new tool to address several interesting technical challenges:

  • Integration – We’re testing how we can integrate the speed test beta with other existing tools that do things like DOCSIS and Radio Frequency (RF) health checks (the quality of the connection from the home to our network), check whether a cable modem is capable of delivering a customer’s speed or needs to be replaced, etc., building on some of what we have learned via our Speed Experience Beta site.
  • Gigabit speeds – As we continue to introduce new, faster speed tiers, including gigabit class speeds, we’re looking to optimize the test for those higher speeds, which presents some interesting technical challenges that researchers are exploring.
  • HTML5 – Given our focus on HTML5 development, we wanted to explore designing a speed test using that standard.
  • Mobile and tablet screens – With our customers seamlessly moving between screens in their homes, we’re testing how we can optimize for smaller mobile and tablet screens.
  • Research Collaboration – A great deal of interesting performance and quality of experience (QoE) research is happening these days, and we wanted a platform that enabled us to collaborate closely with researchers in this area, while using their expertise to improve or develop new measurement tools and methodologies.

We will also continue to work with measurement researchers from around the world – many of whom we have gotten to know well via the Comcast Innovation Fund – to study the resulting measurement data that the testing tool returns.

The beta site is live. Users can provide feedback here. We’ll be back with more information on the hackathon, open source repository, and other developments as our beta testing progresses.