To determine the day that you joined reddit, go to your profile, (eghttp://www.reddit.com/user/TYPEYOURUSERNAMEHERE/ ) find where it says "redditor for XX years" and hover your mouse over the section in the sidebar that says "XX years". A tooltip will appear displaying the exact date and time of your account creation. You receive a cake icon against your name every year on that same day (give or take a few hours).
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