Make sure not to do any typing or other tasks except moving the mouse as this can trigger the responsiveness of the system. Latency is under the WIFI bar. This code is unique in its own way. Each "WIFI" you hear is recorded and timed, meaning it checks your responsiveness and internet. Language tools are also used to check. If you don't hear the, "WIFI" you probably don't have any WIFI. Make sure you leave your cursor on the stage! It does not matter if you have fullscreen or not though. Surprisingly, it's fairly accurate. I would recommend this wifi checker though: https://scratch.mit.edu/projects/677686773/ because its more advanced and can tolerate average latency and other features that don't come with this wifi checker. They both match in wifi speeds though mostly. Latency levels may stutter. Not that sensitive actually. Number rating: =0 - NASA wifi? ~100 really good network ~200 nice network ~300 average network ~400 not the fastest ~500 kinda bad ~600-900 laggy ~<1.5 really laggy <~2 horrible wifi <~3 you are running on a potato