Happy Eyeballs Webtester
A test run with 10 repetitions usually takes less than five minutes (10 x 5s sleep + measurements).
Depending on your browser and device this might vary significantly.
One repetition uses about 15 kB of data. Therefore a test run with 10 repetitions uses about 150 kB.
Currently we collect the measured results together with userAgent, and vendor information.
We do not collect or store your IP addresses as part of this measurement.
If you want to help us to interpret the results you can describe the network environment as part of the device and user information input field.
Measurement results are not transmitted automatically at the end of it. If you want to enable this feature, check the "Auto Transmit Results" box. If it's not checked you can transmit your results after the measurement ended.
Measurement Information
We setup a server with as many unique IPv4 and IPv6 addresses as measured delays.
Each delay has a corresponding IPv4 and IPv6 address bound to all subdomains of a delay-specific domain name.
By using tc netem we delay the traffic for the IPv6 address by the configured amount of ms.
This enables us to test how browsers deploy Happy Eyeballs.
We randomize domains in order to prevent caching effects on the browsers side.
The measurement without randomization shows us if the browser does any caching or uses performance measurements to select IP versions.