Level of toner....

[linardni]

How may I know the level of toner in cartridge of HP Laserjet 1020 printer?

[ilugd]

if the driver or the software provided by the company doesn't show toner level, you are out of luck.

But if the toner level is going down and is dangerously low, you can see the difference in the printouts and get a new toner.