Display HR/HRV in real-time on my computer monitor

I’m trying to figure out how to display my average heart rate (or HRV) in real time on my computer screen.
My goal is to monitor and control my stress levels in real time while at the computer. Thus my hands need to be free (i can’t use a finger device).

I currently have a TomTom Spark 3 watch and have reached out to them about using their API/sdk but I suspect this may be limited to sync’ing applications.

The Polar chest strap HRM seems to have a lot of support, but the only interface I’ve found to connect it to my computer is this one which is discontinued.

Any advice?

(and I’ll post a report on my solution once I figure it out)

Polar chest straps support the standard Bluetooth Smart heart rate profile, so as long as your computer can connect to Bluetooth devices (and the driver supports BLE), you have all the hardware you need. If not, you can a Bluetooth USB dongle.