The claim

“what are the odds of you actually exsisting?”

There is no single rigorous, agreed-upon probability for “the odds of you existing” because the answer depends entirely on how “you” and “odds” are defined and what reference class and assumptions are used.

Some popular framings (e.g., multiplying probabilities of ancestral pairings or specific sperm/egg combinations) can yield extremely tiny numbers, but they rely on unrealistic independence assumptions and ignore that many different genetic and environmental paths could still produce a person meaningfully considered “you.” In philosophy and anthropology, the question also implicates the “reference class problem” and issues like the Doomsday argument/anthropic reasoning, which show that different reasonable reference classes produce different probability statements. In biology, each conception involves enormous numbers of possible sperm, but turning that into “odds of you” is not well-defined without specifying identity criteria (exact genome, same memories, same life history, etc.). Therefore, the claim that there is a specific, rigorous numerical “odds of you existing” is not currently something that can be fact-checked as true or false; it is fundamentally under-specified.