Sexual Relationships 
Sexual Health 
As a way to deal with trolls, here is a statistical breakdown of penis size in the United States.
First off, I would like to say that the mean (connotated as μ later on) is based off of the January 2015 study that established that the average penis length in the US was 5.17 inches long.
References:
https://www.medicalnewstoday.com/articles/271647.php
https://news.sciencemag.org/biology/2015/03/how-big-average-penis
https://www.cnn.com/2015/03/05/health/normal-penis-size/
That said, there are constantly questions on this site, and on the internet in general asking "I'm 15 and my penis is 500 inches long, is this normal?". And one thing that the study also published along with the average length, is the standard deviation, which is 0.8 inches. To explain this simply, Standard Deviation (later connotated as σ) is a number that states the distance a result is from the average.
Now, penis size on a bell curve has a mean (μ) of 5.17, and a Standard Deviation (σ) of 0.8. That means that the exact center average size of the penis in the US is 5.17 inches long, and 68% of ALL penises in the US will fall between 4.37 inches and 5.97 inches long. This is quickly notated as (μ ±σ), or 5.17 ±0.8.
When you look at this bell curve, you will see that the mean is directly in the center, and the farther you get from that center the smaller the amount of results in that category. The way this is broken down for penis size is exactly the same. 68% of all penises in the US will be within 0.8" of the average, 95% of penises will be within 1.6" of the average, and 99.7% of all penises will be within 2.4" from the average. To break this down further, we can say:
-68% of penises are between 4.37" and 5.97"
-95% of penises are between 3.57" and 6.77"
-99.7% of penises are between 2.77" and 7.57"
Now, what does this mean exactly? One, if you are within a single standard deviant of the mean, you fall within the "size doesn't matter" area because you aren't far enough from the average for it to really have an affect on anything. But more importantly, two: we can easily calculate the chance of the ridiculous internet claims actually being true.
Let's take the most common internet penis size claim, 8 inches, and look at the chance of that person not being full of shit. (8.0-5.17)=2.83, (2.83/0.8)=~3.5
- A penis being μ ± 3.5σ has a population range of 0.999534741841929. Which means that only 1 person in 2149 people will fall that far from the mean. Only one in 2149 men in the US have a penis of at least 8 inches.
Now, in case you're wondering where you fall in on this scale, or how likely someone making a ridiculous penis claim is to be lying, I have broken down a short list of sizes and a rough corresponding probability.
About 1 inch, σ=5.21, (μ - 5σ) ~1 in 1,744,278
About 2 inch, σ=3.96, (μ - 4σ) ~1 in 15,787
About 3 inch, σ=2.71, (μ - 3σ) ~1 in 370
About 4 inch, σ=1.46, (μ - 1.5σ) ~1 in 7
About 4.5 inch, σ=0.84, (μ - σ) ~1 in 3
About 5 inch, σ=0.21, (μ) ~2 in 3
About 5.5 inch, σ= 0.33, (μ+0.5σ) ~2 in 3
About 6 inch, σ=1.03, (μ + σ) ~1 in 3
About 6.5 inch, σ=1.66, (μ + 1.5σ) ~1 in 7
About 7 inch, σ=2.29, (μ + 2σ) ~1 in 22
About 7.5 inch, σ=2.91, (μ + 3σ) ~1 in 370
About 8 inch, σ=3.54, (μ + 3.5σ) ~1 in 2149
About 9 inch, σ=4.79, (μ + 4σ) ~1 in 15,787
About 10 inch, σ=6.04, (μ + 6σ) ~1 in 506,797,346
About 11 inch, σ=7.29, (μ + 7σ) ~1 in 390,682,215,445
I am going to stop there, as any further becomes pretty much incalculable. The world's largest penis, 13.5 inches long belonging to Jonah Falcon is almost 10.5σ from the mean, which is a deviation nearing impossibility.
According to these statistics, there MIGHT be one single man in the United States with a penis that is 10 inches long or more.
Probability of results taken using:(https://en.wikipedia.org/wiki/Standard_deviation#Rules_for_normally_distributed_data )
I understand that this is delving far more into this particular subject than is needed, but I did this as a way to show that with most of these claims on here, say 8 inches again as example, only have a 0.00047% chance of being true. And something as ridiculous as a 10 inch penis only has a chance of 0.000000002%.
Now, the average length per country does differ slightly, but for locations such as the US, UK, or Canada, these number are largely the same.
What Girls & Guys Said
12 49i think the standard deviation is more like 1.37 inches but i guess i doesn't matter anyways.
I can say for sure there is more than one man that is 10 inches. I am a big cock whore for sure and I seek out large cocks. I find more small than medium or large, but there are more guys than you think that are in the 7-10+ inch range in the U. S.
I'm about 6.1, but I wish I was like 9 inches
8 INCHES! YES!!! 1 in 2149!
So in other words it's automatically a lie if you say you're big? Lol. Okay buddy.
Jesus christ this is ridiculous. No, it's highly improbable that you aren't lying, and it would be a safe bet x-1/x times you say someone was lying about it. You really should stay in school if a concept that simple escapes you. One million people say they won the jackpot, only one person did. So 999,999 out of 1,000,000 people aren't telling the truth. Meaning you could say to every single person who said they won the lottery that they were lying, and you would only be wrong once.
Not exactly. What that doesn't account for is just by chance more than one person may have just so happened to win the jackpot out of 1,000,000 people. Perhaps the two were meeting up? Perhaps they know each other? Highly unlikely but it's not impossible, which is my point. It's not impossible for more than one guy on here to have a big penis. It's highly unlikely, but not impossible. You still can be wrong lol.
In fact I've heard a story in which two family members both had winning tickets. Both didn't win the big big lottery I don't think, but the smaller lottery.
The entire point of this article is that while it is possible, the probability of that happening is much smaller than people think. I'm not saying it doesn't happen, just that it happens a lot less.
*Trolls* "So my 12 inch dick isn't large enough?"
Is 5.8 inches big enough?
George Carlin proves that these stats caused the Iraq war.
https://www.youtube.com/watch?v=jMwXR-1oajEMy first had an 8.4 inch penis, I mostly liked the thickness. Length doesn't really matter to me.
Yeah but on the internet 99.7% of guys have a 10 inch dick.
Why? Just why?
Is it just me, or are a lot of men these days gay? I mean, why would anyone give 2 shits about their penis size... unless it's abnormally small?
Most psychologists believe it has to do with the rise of the internet, and having easy access to seeing other men's penises. There didn't used to be as much of a concern about size, because whatever you had you just assumed was average, but now you can see millions of dicks at the click of a button.
I say it's because men are being feminized
People always knew that some people have large penises and some have small... nothing new...
Race may play a role
You included references:
d1l4od7sxc8nwf.cloudfront.net/.../...thumbs_up.gif
Girls care more about girth. So your length stats are pointless..
Size stats are completely pointless to begin with. Knowledge that you have a particular length or girth does nothing if you're bad in bed, or not having sex at all. Length is just what people brag about on the internet.
girth stretches that poon out. Ladies want to know where their dudes fall on that metric, not length. But good effort.
1. Thanks for shitting all over my post. I really really really care about your feedback. 2. Again, caring doesn't mean jack shit. You have what you have.
Yayyy, I'm freakin huge
No one cares!
No, seriously... I'm a freak
No seriously, no one cares.
75% of the ladies care 8======================»
No, no one cares.
There is a 0% chance that you are right 86% of the girls want a peek at mine 16% of the guys want a peek at mine (yuck) there is a 99% +/- .0005% that I will poop in the next hour
oh yeah now all the guys here have a python
Excuse the pun, but I think you're lowballing it there. No way am I in the top 5 percent with 7 inches.
No one asked you to state any size, real or imagined. This is merely a statistical breakdown based off of the standard deviation and mean provided by the most recent study on US penis size.
Your stats are junk. 13.5 inches should occur like once out of every quadrillion times according to you
Rule number one regarding extremes: all calculations are extreme estimates with little reliability. The world record has a low chance of happening? Who would have guessed. Maybe that's why it's the world record.
If you're being honest, it isn't that weird to be in the top 5%. After all, one in twenty are going to be there.
The problem is you are confusing the map with the territory. Biological aspects do not perfectly conform to theoretical parameters. In real life the curve has bumps and 'tails' and is not a good approximation at the extremes. Compare the theoretical curve for height to actual height measurements for example. The average might be 5'10 but at four standard deviations out there are not an equal number of very tall and very short people.
So the curve is a good tool for making general observations about biological traits but you can't use it to 'prove' anything about how common extremes are.
I understand that frequency is iffy at extremes even before trying to apply them to the real world. This is merely to show that the commonality of these things is much, much lower than is believed on the internet.
Oh yeah, I'd grant that but I would be very surprised if there weren't more very large than very small ones.
Yeah, there definitely are. Since there's a set minimum and theoretically no maximum, there's a lot more that are bigger than there are smaller.
Also biologically, a 1" long penis is not going to work as well at reproduction as a 9" one, though neither is optimum so there is probably more selection pressure against the micropenis.
Yeah, I could have gone a lot farther into this and consider things like biological favoritism and breeding rights (which is why in places like the Congo, where clothing was not normative until recently the average penis size is larger), likelihood of impregnation, likelihood of volunteering for being measured, margin of error and other variables like that. But honestly, it's not worth doing grad level work for a side project I'm anonymously posting to the internet.