From Encyclopedia Dramatica
- Not to be confused with 99% (person)
99.9 is a number less than 100, but pretty much the same number; nobody cares about the difference.
99.9% (variantly, 90% 99%, 99.99%, etc) is a figure expressing absolute certainty, but leaving a slight chance of doubt to cover one's ass in the event that one happens to be talking out of it. Much like the at least 100 years ago and no more than 99 years ago clauses, but used by anyone from advertisers to ignorant forum trolls in an attempt to validate an arguement otherwise based on hearsay and assumption. 99.9% of the time, "99.9%" holds no factual grounds, which as a matter of fact doesn't ensure any lulz, since the people desperately trying to cover up their Green Day-inspired lies are usually not worth caring about anyhow.
- "99.9% of the time Wolverine would pwn Spider-Man kekekekeke"
- "Guaranteed to kill 99.9% of all germs!!!"
- "99.9% of teen marijuana usage can be attributed to bad parenting."
- "You have a 99.9% chance to get pwnt on the internet."
- "There is a 99.9% chance that you will fail 50% of the time."
In Contrast to "100% Sure"
To be "100% sure" of something, is to have no question in your mind that what you believe you know to be true. If someone says they are "100% sure" of something, chances are they are 100% full of shit.