We finally have a direct comparison from the new (canon) novelisation of the film; The Empire Strikes Back: So You Want to Be a Jedi?
“Sir! The odds of surviving a direct attack on an Imperial Star Destroyer are—”
“Shut up!” Leia shouts.
But in case you want to know, the odds of the Falcon surviving an attack on an Imperial Star Destroyer are about the same as the odds of a lame, half-blind bunny surviving an attack on a hungry tiger. Give or take.
The ship dives at the Destroyer, lasers blazing.
It is one brave bunny.
The film's junior novelisation also gives us a fair indication;
“You’re going to attack them?!” Leia said with alarm as Han jumped back behind the controls.
When Han didn’t reply, C-3PO informed him, “Sir, the odds of surviving a direct assault on an Imperial Star Destroyer —”
“Shut up!” Leia shouted.
Han banked hard to port, then made a steep, twisting turn. In the next moment, the Falcon was racing toward the infinitely more powerful Destroyer.
Although it's clearly an act of hyperbole to state that the Destroyer is infinitely more powerful, it stands to reason that the odds are essentially 0%