My biggest win ever was $10k hitting a major jackpot on 1xbit casino. But it has been 3 years already and frankly speaking i busted the rest amount after withdrawing $6k. I was playing a slot game and base bet was $10 each roll. That time my bankroll was around $3k worth.
But i want to tell everybody that it doesn't matter how big you win in gambling, it is important how much cash you managed to withdraw in the end.
Right now i controlled my gambling habit and not playing at that much as before.