The term speed test can be misleading. Most speed tests on the Internet are actually testing capacity, which isn't indicative of the user experience.
Our speed test is actually a throughput test. Throughput refers to the amount of data transferred from one point to another within a given amount of time.
Throughput is a key measure of the performance of a network connection, illustrating the actual speed at which data is being transferred, as opposed to the theoretical maximum, or "bandwidth capacity," of the connection.
In a sense, you can consider bandwidth as the width of the highway (the maximum capacity), and throughput as the actual speed of the cars on the highway (the actual data transfer rate achieved).
It's important to note that a variety of factors can impact throughput, including but not limited to the quality of your network hardware, the speed of your Internet service, network congestion, the protocols being used, the distance data must travel, and the size and type of data being transferred.
This speed test is conducted in accordance with RFC 6349, the guiding framework for throughput measurements, to simulate a realistic user experience. Unlike many applications that operate exclusively on a per-user basis, our test aims to yield the most accurate, real-life results.
Contrastingly, user capacity tests - commonly employed by most internet speed tests - tend to display higher results due to their cumulative nature. Although this might seem advantageous, the aggregation of user results can be misleading. To illustrate, it's like assuming that ten cars stuck in a traffic jam, each crawling at 1mph, is equivalent to one vehicle smoothly cruising at 10mph.
It's important to note that the service Internet Service Providers (ISPs) offer is not guaranteed over WiFi - use a wired connection if possible - and is classed as "up to", for example "up to 300Mbps".
ISPs phrase it that way because they know achieving 300 Mbps consistently is not going to happen as data can only travel so fast for a given distance, known as latency.
Let's say you're browsing your favorite website. Your computer sends a request to the server asking for the webpage. This request travels across the internet, gets to the server, and the server then sends back a response with the data for the webpage. This response is broken up into many small data packets to be sent over the internet. The distance is measured in milliseconds and is referred to as the round-trip-time (RTT).
The RTT determines the maximum throughput ("speed") that the data can travel. If the RTT is 65 milliseconds the maximum throughput is 8 Mbps. This doesn't change even if you pay for a 1 Gbps connection.
SLA stands for service level agreement. When you sign up for Internet with a provider, like Verizon or AT&T, they provide you with a specific service level.
This maybe something like up to 300 Mbps download and up to 40 Mbps upload.
Internet Service Providers (ISPs) can employ several strategies and technologies to manage and provision Internet traffic on their networks. These practices are designed to help ensure efficient, stable, and secure delivery of services to their customers, but this often leads to a degraded service, especially if they are over-subscribed (meaning there are more users than the network can reliably hold).
Our SLA bandwidth metric is an average of the high and low points of the speed test, which gives you an idea of how the ISPs policies are affecting the overall "speed" you experience.