Internet Speed Test
Measures download speed, upload speed, latency and jitter by sending real data between your device and this site. It only starts when you press the button, and it can use up to the data shown under Size.
What the result means
This is the speed between your device and this one server, not the speed your provider sells you or what you'd get from every other site. Your distance from the server, other devices on your network, a VPN and Wi-Fi quality can all lower it.
Traffic passes through Cloudflare on the way. Latency and jitter include the trip from Cloudflare to the server, so they're higher than a ping to your nearest Cloudflare data centre. Cloudflare can hold on to uploaded data before passing it on, so upload only counts data the server has confirmed receiving.
Each test is limited to a fixed amount of data and about eight seconds in each direction, to keep this free tool from using too much of the server. On very fast connections the limit can arrive first, and the result then tells you so. Speeds are averages over the whole transfer, in megabits per second.