[Tonkin]

You're supposed to at least as deep to make your thighs parallel with the ground.

But the further you go, the harder it is. So some people consider "ass to the grass" to be a true squat, like what you are doing.

But I think as long as your upper legs go as far as parallel with the ground, you're good!

Although some people do partial squats, which are very shallow, but that can be for other reasons, like rehab, working other muscle groups etc.