OpeNoise is one… it will need calibration but if you weren’t concerned about actual dB readings you could use it uncalibrated

It says that the program depends on a non-free network service. Does that mean there is a subscription or other type of payment involved?

I’ve stopped using Reddit unless it comes up in a search for something I am looking for. At that point, I just read that one post and replies to find what I am looking for.

We often forget that sites like Reddit and Facebook could completely be shut down if people stopped using them. The people provide the content for those sites. Those sites need us, but we don’t need them!

Any program that communicates with USB connected hardware via a non-standard, Windows only USB driver as provided by the hardware vendor. In other words, you can’t just plug a device into any OS and start programing it via a standard USB driver.