At what age did you know (or become) an atheist? Or, at least question the existence of a "god".
I was never really brought up with much religion (thank Gawd), and my parents were Muslim. I was always a skeptic by nature, but for a very short time when I was a kid, I used to pray at night, mostly because I saw it in movies.
One night, and I only did this a few times total, I just realized "this is stupid, and I'm just talking to myself", and never looked back. Been an atheist ever since.
Then as I got older, logic, reason, common sense, all played a role to only solidify my disbelief in anything supernatural, including "god', or Gawd, as I call it.
I was raised Catholic, required to attend 8am mass every Sunday, never enjoyed it or felt enriched by it. It was a chore and felt like a waste of time, even as a child and teen. I seriously started questioning whether I believed any of it in my early to mid 20s. I explored other denominations to see if they connected with me more. I thoroughly read the Bible, start to finish. And by late 20s, I finally came to the realization that I didn't believe in any of it and I was getting myself stressed out trying to force it. I let go of the need to believe, and felt free.
I came to this realization at the age of 65. I went to Catholic high school and entered a convent. Thus, I was super brain washed and it took some time to become unfettered. I have to say, it was quite unsettling to learn that foundational truths I held were not true at all. It has been shattering. Here is a bit of convent trivia. Others who left the convent are now humanists and have no belief in God.
The earliest I can remember is 15. At prep school we had many juvenile discussions about such things.
I questioned the existence of god in my early to mid 30s. I became an atheist at 41. I'm an happier person now and glad to be free of the bs of religion/god. I know I have put this in a number of comments I have made on this web site, but I wish I became an atheist earlier in life. Like my early 30s for example.