Lens tightness can be examined with the push-up test. Using a continuous scale from 0 to 100 per cent, lens tightness of 50% indicates optimal lens behavior at push-up, 100% would indicate the lens is too tight (almost impossible to dislodge) and 0% would be a lens which is too loose (slides from the cornea without lid support).
Lens tightness of slightly less than 50% (rather looser than tighter) is seen as desirable for silicone hydrogel contact lenses.