It's really not very far, maybe 15 meters.

I'm actually super annoyed that popular devices no longer show bluetooth signal strength at all... it's completely absent from the UI.

Impossible to know how well connected my headphones are when I keep hearing popping or distortion... you need special apps to realise how weak the connection actually is (and how absurdly busy the environment is: there are so many bluetooth devices around us.. it's crazy!)