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Your Internet Service Performance

Comcast provides residential customers with a variety of high-speed Internet plans from which to choose, with download speed tiers ranging from up to 5 megabits per second ("Mbps") to up to 300 Mbps (in select markets) and upload speeds ranging from up to 768 kilobits per second ("kbps") to up to 25 Mbps on our DOCSIS 3.0 and 3.1 cable networks. In select markets, we also offer a fiber-based service with symmetrical download and upload speeds up to 2 gigabits per second ("Gbps"). To see the plans currently available to you, please go to http://www.comcast.com/internet-service.html.

Comcast provisions its customers' modems and engineers its network with the goal of enabling customers to enjoy the speeds to which they subscribe. Comcast also provides minimum system recommendations for each of the speed tiers it offers, which can be found at https://customer.xfinity.com/help-and-support/internet/requirements-to-run-xfinity-internet-service. However, Comcast does not guarantee that a customer will achieve those speeds at all times. Comcast advertises its speeds as "up to" a specific level based on the tier of service to which a customer subscribes. As Comcast makes clear in its advertising and pricing information disclosures, "Actual speeds vary and are not guaranteed." The "actual" speed that a customer will experience while using the service depends upon a variety of conditions, many of which are beyond the control of Comcast as an Internet Service Provider ("ISP"). These conditions include:

  1. Performance of a customer's computer, including factors such as its age, processing capability, operating system, the number of applications running simultaneously, and the presence of any adware and viruses.
  2. Type of connection between a customer's computer and modem. For example, in-home wireless connections between the computer and the router or modem may be generally slower than wired connections. In-home wireless connections also may be subject to greater performance fluctuations, caused by factors like interference, attenuation, and congestion. Comcast recommends that customers confirm that their in-home wireless connections are able to support the speeds that Comcast's services deliver. Certain older in-home wireless connections and routers cannot perform at the speeds delivered by Comcast's higher speed tiers. Customers can purchase their modem and router at a retail outlet, or they can lease the necessary equipment from Comcast, though even wireless routers leased from Comcast are subject to some of the same limitations mentioned above.
  3. The distance and time it takes packets to travel between a customer's modem and their final destination on the Internet, or their point of origination and a customer's modem, including the number and quality of the networks of various operators in the transmission path. The Internet is a "network of networks." A customer's Internet traffic may traverse the networks of multiple providers before reaching its destination, and the capabilities of those networks, as well as the capacity of the facilities the edge provider (i.e., any provider of content, applications, or services over the Internet) has chosen to route its traffic to Comcast's network (and the interconnection capacity it has arranged), may affect the overall speed of an Internet connection.
  4. Congestion or high usage levels at the edge provider or destination. When you access an edge provider or particular destination that is being visited by others at the same time, you may experience a slower connection if the edge provider or destination does not have sufficient capacity to serve all of the visitors efficiently at the same time.
  5. Gating of speeds or access by the edge provider or destination. To control traffic or performance, many edge providers limit the speeds at which a visitor can download from their site. Those speed limitations will carry through to a customer's connection.
  6. The performance of the cable modem you have installed. Modem performance may degrade over time, and certain modems are not capable of handling higher speeds, such as DOCSIS 2.0 devices or early DOCSIS 3.0 devices. Comcast has a Device-to-Product Enforcement ("DPE") program to identify when customers may be using incompatible or old modem devices, whether leased or owned, and provides instructions on how to obtain new modems capable of receiving the speeds and features included with their service. Additionally, Comcast encourages its customers to promptly contact customer service if they have any concerns about their modem performance or speed capabilities. Please visit MyDeviceInfo for information regarding cable modems approved for use on Comcast's network and to determine which devices can support various speeds.

Speed

The Federal Communications Commission ("FCC") conducts an ongoing, rigorous study of the performance of the largest ISPs in the United States ("Measuring Broadband America"), including Comcast. The most recent report from this study can be found at https://www.fcc.gov/reports-research/reports/measuring-broadband-america/measuring-fixed-broadband-report-2016. The FCC determined that Comcast's XFINITY Internet services deliver, on average, over 100 percent of their advertised downstream and upstream speeds during the busiest periods of the day, known as "peak" times, during sustained testing. Peak times are Monday through Friday from 7:00 p.m. to 11:00 p.m. local time.

Below are the median download and upload speeds by tier. Unless a speed tier is noted with an asterisk (*), the reported information comes from the latest FCC study. We are including the FCC's measurement of the 105 Mbps speed tier, which we no longer offer, on an interim basis until internal measurements of our 100 Mbps speed tier are completed, but we do not expect the results to differ significantly. Service tiers noted with an asterisk were not included in the FCC's study either because they are newer products with limited availability or they do not meet the study's reporting requirements. For these noted tiers, the information below is based on data compiled independently by Comcast using a largely similar testing methodology.

Speed
Down (Mpbs) Up (Mbps)
Tier Measured Tier Measured
5* 5.95 1 1.21
10* 11.8 1 1.21
10* 11.8 2 2.4
25 28.90 0.768 0.89
50 57.56 5 5.91
75 85.38 10 11.87
105 110.81 5 5.91
150 151.65 20 **
200* 212.2 10 11.5
250* 265.1 25 29.7
300* 318.2 25 29.7

*Based on independent measurements by Comcast

**Not reported by Measuring Broadband America


Comcast's XFINITY Internet services also deliver over 100 percent of their advertised downstream and upstream speeds during periods of time when Internet usage is generally lighter, known as "off peak" times, during sustained testing. Below are the Comcast median speeds by tier during off peak times:

Speed
Down (Mpbs) Up (Mbps)
Tier Measured Tier Measured
5* 5.95 1 1.21
10* 11.8 1 1.21
10* 11.8 2 2.4
25 29.36 0.768 0.90
50 58.59 5 5.93
75 88.61 10 11.89
105 120.05 5 5.93
150 168.29 20 **
200* 224.3 10 11.7
250* 292.5 25 29.9
300* 336.5 25 29.9

*Based on independent measurements by Comcast

**Not reported by Measuring Broadband America


While individual experiences may vary, the FCC's tests have consistently confirmed the quality of Comcast's XFINITY Internet services.

You also can test your speeds yourself. Comcast offers its customers the ability to test the speeds that they are receiving on Comcast's network from the customer's computer to test sites located throughout Comcast's network. Simply go to http://speedtest.xfinity.com to test your connection. These tests are heavily dependent on several of the factors outlined above, especially the customer's in-home Wi-Fi network. Therefore, these tests do not necessarily reflect the performance of the Comcast network alone.

There are other speed tests that measure Internet performance. We have provided links to a few of these sites below for your reference. Please note, however, that all speed tests have limitations and flaws. Each of these tests measures limited aspects of an ISP's speed and therefore must be seen as a guide rather than definitive measurements of performance.

Latency

Latency is another measurement of Internet performance. Latency is the time delay in transmitting or receiving packets on a network. Latency is primarily a function of the distance between two points of transmission, but also can be affected by the number and quality of the network or networks used in transmission. Latency is typically measured in milliseconds, and generally has no significant impact on typical everyday Internet usage. As latency varies based on any number of factors, most importantly the distance between a customer's computer and the ultimate Internet destination, it is not possible to provide customers with a single figure that will define latency as part of a user experience. Comcast has no basis for saying what level of latency should be expected by any particular user at any particular time but notes that the measured results from Measuring Broadband America as to past performance are perhaps the closest one can come to identifying expectations of future performance as well.

Measuring Broadband America measures latency using packet tests that calculate the time it takes for packets to travel from a customer location to a target test node and back. Below are the Comcast median latency results by tier during peak times (as defined above), during sustained testing:


Speed Tier (Mbps) Latency
Down 5* 12.3 ms
Down 10* 16.4 ms
Down 25 20.90 ms
Down 50 25.20 ms
Down 75 18.74 ms
Down 105 23.98 ms
Down 150 19.20 ms
Down 200* 19.7 ms
Down 250* 24.3 ms
Down 300* 39.1 ms

*Based on independent measurements by Comcast


Below are the Comcast median latency results by tier during off peak times, during sustained testing:


Speed Tier (Mbps) Latency
Down 5* 11.7 ms
Down 10* 13.7 ms
Down 25 19.83 ms
Down 50 24.96 ms
Down 75 18.46 ms
Down 105 23.67 ms
Down 150 18.75 ms
Down 200* 20.2 ms
Down 250* 23.2 ms
Down 300* 37.3 ms

*Based on independent measurements by Comcast


These results do not define latency as part of a particular user experience because: (1) the results include time spent traversing networks not controlled by Comcast; and (2) the geographic distance between any given user and the target node may vary greatly from those employed in Measuring Broadband America. Customers can test the latency characteristics of their service at http://speedtest.xfinity.com. Of course, this test also may reflect limitations in a customer's home network (especially Wi-Fi) and computers, and therefore will not necessarily reflect the performance of the Comcast network alone.

There are other latency tests available on the Internet. As previously explained, however, all tests have limitations and flaws, and therefore must be seen as a guide rather than definitive measurements of performance.

Packet Loss

Packet loss is a third measurement of Internet performance. Packet loss is the percentage of packets that are sent by the source but not received by the destination. This is sometimes due to congestion along the route but may also reflect an impairment in a customer's home network, including their Wi-Fi and coaxial cable network as well as the connection from the customer's home to the Comcast network. Customers should diagnose their home network for possible repair if packet loss is high. Packet loss is also a normal part of the Transmission Control Protocol (TCP), and signals to a sender to slow their sending rate to adjust to available bandwidth along a network path. As a result, a small amount of packet loss is expected and normal, but it is unlikely to directly affect the perceived quality of applications that request retransmission of lost packets, such as web browsing and email. In addition, measures to further reduce packet loss would require unacceptable increases in latency. However, packet loss may affect the perceived quality of applications that do not request retransmission of lost packets, such as VoIP phone calls and video chat. Nevertheless, packet losses of a few tenths of a percent are sufficiently small so that they are unlikely to significantly affect the perceived quality of these applications. The Internet's technical community continues to debate the merit and meaning of packet loss measurement. Comcast has no basis for saying what level of packet loss should be expected by any particular user at any particular time but notes that the measured results from Measuring Broadband America as to past performance are perhaps the closest one can come to identifying expectations of future performance as well.

Measuring Broadband America includes packet loss tests performed using packet tests that measure the time it takes those packets to travel from a customer location to a target test node and back. Packets not received back within three seconds of sending were treated as lost. Below are the Comcast average packet loss results by tier during peak times (as defined above), during sustained testing. Comcast currently does not have packet loss data for our 5, 10, 200, 250, and 300 Mbps services tiers. However, based on the MBA data, we expect packet loss to be in the range of 0.08% to 0.10%.


Speed Tier (Mbps) Packet Loss
Down 25 0.10%
Down 50 0.08%
Down 75 0.10%
Down 105 0.06%
Down 150 0.10%

Below are the Comcast average packet loss results by tier during off peak times, during sustained testing. Comcast currently does not have packet loss data for our 5, 10, 200, 250, and 300 Mbps services tiers. However, based on the MBA data, we expect packet loss to be in the range of 0.06% to 0.10%.


Speed Tier (Mbps) Packet Loss
Down 25 0.06%
Down 50 0.10%
Down 75 0.07%
Down 105 0.07%
Down 150 0.07%

Customers can test their packet loss by performing 'ping' tests or other tests. As previously explained, however, all tests have limitations and flaws, and therefore must be seen as a guide rather than definitive measurements of performance. These tests are heavily dependent on several of the factors outlined above, especially the customer's in-home Wi-Fi network. Therefore, these tests do not necessarily reflect the performance of the Comcast network alone.

XFINITY WiFi

In addition to the residential or commercial Internet service that you enjoy at your home or office, Comcast provides its Internet subscribers with XFINITY WiFi, which allows XFINITY Internet subscribers to access the Internet when they are at one of the many XFINITY or Cable WiFi hotspots. Comcast engineers the underlying network to deliver high-performance access to the Internet. However, the performance you experience, once you connect to the hotspot, may vary based on any number of factors, such as the number of other subscribers trying to use the same hotspot at the same time, your computer or wireless device, your Wi-Fi receiving antenna, your distance from the hotspot router, attenuation from walls and foliage, and interference from other devices using the same spectrum, in addition to many of the factors already mentioned above. These Wi-Fi hotspots use spectrum that the FCC has allocated for "unlicensed" use, which means that our use of this spectrum is not protected from interference from other devices using the same spectrum in the same geographical area. This makes it inherently difficult to predict the kind of performance you can expect. Therefore, this service is provided solely on a "best efforts" basis.

Additional information