I have a credit score of 813 is that good?

Where did you get your score from? If Karma it is not a real score.

No, 713 is good. 813 is excellent.

I thought that was impossible :/

Possible, but probably not.

Everyone with a credit score has several different credit scores. No one has only one. You didn't say which of your scores was 813.

The scores that actually matter only go up to 850, and almost never go over 805. So if a score is 813, that means it's probably one of the other scores, which don't matter, and are typically 100-150 points higher than the scores that do matter, so your real score is probably a little less than 700, which is okay, but not great.