How to run an internet speed test and read the results

For accurate measurement use a wired connection, a single device and the right server. What do download, upload, ping and jitter mean?

A speed test is the easiest way to gauge the health of your internet connection. But a test run in the wrong conditions can give the impression that your line is slow. Follow these steps for accurate measurement.

Preparing for a proper test

Connect by cable: connect the computer to the modem with an Ethernet cable. Wi-Fi tests are affected by signal strength and interference.
Close other devices and apps: pause streaming, downloads and cloud backups.
Reduce browser tabs and turn off the VPN.
Choose a nearby test server: if possible use one in the same city.
Repeat the test three times and look at the average; also try at different times.

What do the results mean?

Download: the speed at which you pull data from the internet. At least 90% of your tariff speed should be seen on a wired connection.
Upload: the speed of sending data. Critical for video conferencing, backups and live streaming.
Ping (latency): round-trip time in milliseconds. On fibre it is usually 3 to 12 ms; below 30 ms is ideal for gaming.
Jitter: variation in ping. Below 5 ms is considered good; high jitter causes dropouts in video calls.

If the result is far below tariff speed

First turn the modem off for 30 seconds and on again, and plug the cable into another port. If it is still low, save the measurements as screenshots and open a fault ticket in the customer portal. Our technician tests the line remotely and, if needed, measures on site.

Mbps and MB/s confusion

Tariff speeds are in megabits per second (Mbps). File download programs usually show megabytes per second (MB/s). 1 MB/s equals 8 Mbps. So a 500 Mbps line can theoretically download about 62 MB per second.

Keep records

For recurring problems, keeping a record with dates, times and results lets us solve them faster. The speed measurement tool in our customer portal archives measurements automatically.

Testing on mobile devices

If you test from a phone or tablet, bring the device next to the modem, connect to the 5 GHz Wi-Fi network and close other apps. Because of processor and Wi-Fi card limits, mobile results may be lower than a wired test from a computer; that does not mean your line is slow. Use phone measurements only to compare Wi-Fi coverage.

When should you complain?

If, on a wired connection, outside peak hours and across several tests, you get results below 90% of your tariff speed, you can open a fault ticket under our service quality commitment. Once the ticket is opened your line is tested remotely and, if needed, measured on site. If the fault stems from infrastructure, a fee refund applies.

Note: a speed test only shows the connection quality at that moment. Three or five measurements on different days and at different hours reflect your line's real performance much more accurately; by adding them to the speed log in the customer portal you can speed up fault handling.