Knowing more about the biceps will help you to grow your arms because you'll be able to select the most optimal muscle-building movements.
But before we get into the training tips, let's answer the question that's probably on your lips: Are 11 inch biceps small?
The answer, as you'll soon learn, depends. Specifically, your gender, height, weight, and body fat level will determine whether or not your 11 inch arms are big, small, or normal.
Our arm size chart will give you a rough estimate, but that data doesn't take into account the factors that I just mentioned.
Are 11 inch biceps small?
In general, yes, an 11 inch bicep circumference is quite small. However, to what extent 11" biceps are big or small depends on the physical factors mentioned above (age, height, weight, etc.)
For example, if you're a 5'2" male or female with a normal body fat level, then having 11 inch arms is actually pretty normal if you work out regularly.
Yes, the average is around 12-13 inches, but being an inch smaller than average is by no means abnormal. 
Of course, if you're of a standard height, then 11 in biceps will look really skinny, especially if that's your flexed measurement.
While you shouldn't be overly concerned with the appearance of your physique, having 11 in arms means that your biceps and triceps muscles are less developed than average.
Don't worry, though; you can easily fix this lack of muscle mass if you're willing to make a few small lifestyle changes (more on that later).
Are 11 inch arms a normal size for a female?
It depends on the body fat level of the female in question.
If you're quite lean, then it's normal to have only 11" biceps.
However, if you have a lot of body fat and still only have 11" arms, then you're likely either a) very short or b) lacking bicep and tricep muscle mass.
That said, 11 in arms are only just below average for a woman, based on US general population data.
If you're a runner or work out regularly, then there's a good chance that your arms will look lean and toned at 11 inches rather than just thin and stringy.
Are 11.5 inch biceps impressive?
While you might not think that there's much difference between 11 inch and 11.5 inch biceps, gaining half an inch of muscle can make your arms look significantly bigger.
As for whether 11.5 inch arms are impressive or not, that depends on your body stats.
The smaller and leaner you are, the larger such an arm size will look. This is because, at an equivalent bicep size, the arms of shorter lifters will always look more filled out than those of taller lifters because they have better development relative to their genetic potential.
On the flip side, if you're carrying excess body fat and have a taller frame, then your arms will look quite skinny. Whether such an appearance is desirable or not depends on your goals.
Of course, if having 11.5 inch arms gives you an underweight BMI, then you should talk to your doctor so that you can figure out how to safely and effectively gain weight.
How to exceed 11 inch arms
If you want to surpass an 11 inch arm circumference naturally, then make sure that you're following these three fitness fundamentals.
Eat enough calories
Many skinny guys struggle to eat enough calories in order to gain the weight they desire.
Yet, there's no need to eat in a huge calorie surplus in order to gain weight.
Taking in slightly more calories than your body needs to maintain its mass will increase your body weight and, if you train your biceps and triceps, your arm size as well. 
Since your arms are already skinny at 11 inches, you can see quick results by upping your protein and calories.
Just don't overdo it. While it's fine to lose some muscle definition as you gain weight, you should be gaining muscle at a faster rate than body fat if your starting point is lean and skinny.
Lift weights on a weekly basis
Training your arms (and muscles in general) helps to ensure that the calories you consume get partitioned towards muscle growth rather than fat storage.
Of course, direct arm training is the most efficient way to exceed 11 inch biceps in a short space of time, but it's important to train your other muscle groups as well if you want your physique to look proportional.
As for which exercises to do, for triceps, some kind of overhead extension or skull crusher is your best bet because these movements emphasize the long head, which is by far the biggest tricep muscle.
In terms of bicep building, pick an exercise such as an EZ curl or barbell curl that you can progressively overload on a regular basis. There's no need to increase the weight each and every week, but upping the resistance over the course of the months is of paramount importance if you want to see a noticeable improvement in your bicep size.
Get enough sleep
So many lifters train hard and eat a good diet, but then they fall at the final hurdle by failing to get enough sleep.
While muscles get stimulated in the gym, they actually grow outside of the gym when you're resting and sleeping.
So if you want to maximize your progress and exceed your 11 inch biceps, make sure that you're getting 8 hours of sleep per night.
If you had a hard workout the day before, then you could even sleep closer to 9 hours if you think it would be beneficial for your recovery. 
Conclusion: Should you be concerned about having 11 inch biceps?
With the dawn of the internet and modern bodybuilding, more people than ever are concerned about the size and appearance of their arms.
However, unless you have an unhealthily low body weight, you shouldn't be that bothered about how big and muscular your biceps and triceps are.
While 11 inch arms are smaller than average in most cases (except if you're a lean female or teenager), they're not way below average either.
Lean, short individuals naturally have smaller arms than taller people and those with a high body fat level. So unless your 11 inch biceps coincide with an underweight BMI, you shouldn't dwell on the size of your upper arms.
And anyway, by following the advice in this article, you can make your arms (and indeed any other muscle) grow bigger and more toned.
- National Center for Health Statistics. (2016, August). Anthropometric Reference Data for Children and Adults: United States, 2011–2014. Centers for Disease Control and Prevention. https://www.cdc.gov/nchs/data/series/sr_03/sr03_039.pdf
- Iraki, J., Fitschen, P., Espinar, S., & Helms, E. (2019). Nutrition Recommendations for Bodybuilders in the Off-Season: A Narrative Review. Sports, 7(7), 154. https://doi.org/10.3390/sports7070154
- Mateo, A., & Mackenzie, S., MD PhD. (2018, May 23). How Sleep Affects Fitness and Vice Versa. EverydayHealth.Com. https://www.everydayhealth.com/fitness/intimate-relationship-between-fitness-sleep/