Speedtest - internet speed test

What does my internet speed depend on?

Internet speed determines how smoothly you use the network — from browsing pages, through video streaming, to video calls and online gaming. Although the basis is the plan purchased from your provider, the actual connection speed depends on many factors acting simultaneously: from link technology, through the condition of home equipment, to how you connect to the router. Below we explain what most strongly affects the result and why measurements can differ depending on the time of day or location in your apartment. If you want to check how your connection performs in practice, use the speed test available on this page.

The technology that brings internet to your home sets the upper limit of possible speed. Fiber optics today offers the highest and most stable parameters, and additionally symmetrical — meaning similar download and upload speeds. Cable and copper (DSL) connections usually have a lower ceiling and are more sensitive to technical conditions, while mobile internet (LTE, 5G) depends heavily on coverage and transmitter load. When choosing a service, it is worth knowing what technology it runs on, because it most strongly determines what you can expect.

Bandwidth defines the maximum amount of data a connection can transmit per unit of time. If you have a plan with a bandwidth of e.g. 100 Mb/s, this is a theoretical value — the ceiling that the connection can strive for under ideal conditions. In practice, the measured result is often lower, because several factors described further overlay it. Therefore, the parameter in the contract should be treated as a reference point, not a guarantee of constant, identical speed at all times.

The internet is a shared resource, so the number of users using it at the same time matters. During peak hours, most often in the evenings when many people watch video or play games, speeds can temporarily drop. Load appears at various levels: the provider's local infrastructure, as well as on the side of the servers you connect to. If you notice that the connection slows down at specific times, it is most often the effect of increased network traffic.

With copper connections, the further you are from the provider's exchange, the more the signal weakens along the way, resulting in lower speed. Mobile internet works similarly — distance from the transmitter and terrain obstacles affect signal quality and strength. Fiber optics is much more resistant in this aspect, because data is transmitted by light in fiber and attenuation over distance is minimal. This is one of the reasons why two addresses in the same town can have noticeably different connection quality.

Even the fastest connection will be limited by outdated or weak equipment on your end. The router, modem, network card, and even a regular ethernet cable have their limits — an older router may not handle the full package speed, and a damaged cable can lower the result. The Wi-Fi standard that the device supports also matters: newer generations transmit data faster and handle many connected devices more efficiently. If you pay for fast internet but don't see it in measurements, it is worth starting the diagnosis from the equipment.

A wireless connection is convenient but more susceptible to interference than a cable. Walls, ceilings, large distance from the router and household devices like microwave ovens can weaken the signal and reduce speed. Neighbors' networks operating on the same channel also have an impact, which is why in dense housing the 5 GHz band tends to be more stable than the congested 2.4 GHz. To check how much Wi-Fi itself loses, it is best to perform a measurement via cable and compare it with the wireless result.

Test results depend not only on the connection, but also on the condition of the device you are working on. Background applications, ongoing system updates, open downloads or numerous browser tabs consume resources and bandwidth, lowering available speed. An older computer or phone with weaker components may also simply not keep up with processing data. For a reliable measurement, it is worth closing unnecessary programs and making sure that other devices on the network are not downloading large files at the same time.

The simplest way to measure real speed is with a test that checks three key values: download, upload and latency (ping). For the result to be reliable, close applications using the network, connect the device via cable if possible, and perform the measurement several times at different times. Comparing a wired test with a Wi-Fi test will quickly show whether any drops are due to the connection or the wireless network. The speed test available on this page can be performed with one click — check whether your internet achieves parameters consistent with your provider's plan.