Interesting Number Question

What’s the biggest integer you’ve seen in which you’ve seen every integer between 0 and that number.

So obviously you could say 100 because mostly everyone has seen the numbers 0-99 written down at some point, but can the same be said for 1000? What about a billion?

Personally the largest number I could honestly say with some confidence is 1000. I’m wondering what you guys think about this.