Note: I continue to collect data for the survey mentioned below. This post is updated as information changes.
There is an old saying that starts with “every man knows two sizes about himself” and if that man is a bodybuilder it’s a safe bet that one of those sizes is how big his arms are!
Based on the popularity of some of my earlier posts on what is the average bicep size (see When is a Man’s Arm Considered Big? and How Do You Know if You Have Big Arms? for reference) I know that this is a topic of interest for many guys out there – in fact the number one way people find my blog is because they typed “average arm size” or “average bicep size” into their favorite search engine. So, let’s presume you’ve been lifting a while now, you know how big the average bicep is and you know that you compare well to the average Joe on the street. But how big is that dude posing over in the corner of the gym and posting to his Instagram account? Do you match him? That guy looks pretty jacked…how big are his ‘guns?’
Let’s see if we can get some answers to allay your fears and satisfy your curiosity.
Does Size Matter?
The short answer to this question is an emphatic…sort of.
It all depends what you are hoping to accomplish with your training. I’m going to go out on a limb and say that when most men start lifting it’s for one of two main reasons: 1) they want to get stronger (aka the “Charles Atlas Syndrome”) or 2) they want to look better (aka the “what ‘chu doing tonight?” syndrome).
If your goal is strength then yes, to a large degree, size does matter. But not in the way you might think. In general a bigger muscle is a stronger muscle. However, muscle size isn’t necessarily a good indicator of a man’s strength. I’ve known some 175 pound men who regularly outlift guys 50 pounds heavier. But, at some point size will be a factor. For example if a 175 pound man can bench 350 pounds he’s very strong pound for pound but has likely maxed out his capacity. Whereas if a 250 pound man can bench press 400 pounds he isn’t as strong per pound, but he’s got enough mass that he may be able to put up even more weight. It’s a matter of physics – it takes weight to move weight. There’s a reason that weightlifting competitions are divided into weight classes after all.
If, however, you are going for an aesthetic look of some kind. Perhaps to model, compete in bodybuilding, or catch the eye of a certain someone across the weight room, size does matter. You want to obtain proportions which show off your hard work in the gym and stretch your sleeves just enough to look good. But depending on your height and overall basic build you might be able to do this at a much smaller size that you think.
The Big Lie (or What to Really Expect)
The first thing you need to stop worrying about is the average bicep size of pro or any competitive bodybuilders. You don’t have to look far to find claims of exaggerated arm size which can lead to unrealistic expectations among natural lifters who are just starting out. Any bodybuilder worth his salt is going to claim that he has an arm which measures 20 inches (51 cm) or more. Arnold Schwarzenegger, for example, claimed he had a 22″ (56 cm) arm at his peak at a lean bodyweight of 235 pounds (107 kg) and a height of either 6’1″ or 6’2″ (187 cm).
However, even for one of the greatest bodybuilders ever, an arm that size is unlikely. I’m not saying that arms this big don’t exist, as I personally know a bodybuilder who has 20″ (51 cm) arms. But he is admittedly not natural and that measurement is flexed with a pump. To be frank, arms that big usually belong to men with high bodyfat percentages so they appear flat and without shape. Which in part defeats the goal of having big arms -which is to look and be strong.
The sad truth is that despite what you see on the internet or read in the muscle magazines (do they still have those?) you are not likely to get to a true 20″ arm with out extraordinary genetics and chemical assistance (prove me wrong guys – and more power to you if you do).
So, having said all this what can you expect. That’s were my recent survey came in.
Getting some basic information on the arm size of guys who lift for non-competitive reasons was a little difficult. This is in part because apparently hanging out at the men’s locker room of the local Planet Fitness with a tape measure in hand is not only frowned upon, but can even get you a lifetime ban from the place (don’t ask how I know)! These left me to approached men I know in real life and through social media and ask them how big their arms are. To my surprise, most agreed to help out as they were curious, too.
I want to stress that my survey is unscientific. To my knowledge all the participants have lifted for at least five years and some for considerably longer. Weightlifting and bodybuilding is not necessarily their primary athletic activity at this time, but it is included in their regular workouts. A few of the participants are actively trying to build their arms up (6), some are trying to maintain size (3) and the others are just lifting to improve/maintain their health (6). My sample group, though I think diverse, currently only has 19 men in it.
For the reasons stated above, all measurements were self-reported by the participants. There was no consistency in measuring tapes or techniques. The men range in age from 21 years old to 61 years old – but age is not factored into my results. The tallest are 6’3″ (190.5 cm) and the shortest is about 5’5″ (165 cm). I did not factor in weight, bodyfat percentage or other bodily measurements such as chest and waist. However, to my eye at least, all can be considered muscular even if a few are rocking the so-called “dad bod” or, in my case, the “grandad bod.” Most are Americans, but because I was able to gather information through social media some of the participants are men who reside outside of the United States.
Most of the men had a large arm and a small arm. For the purposes of this survey I took the larger arm’s measurement. Four of the men mentioned specifically that their arms had been larger in the past but they had lost size during the pandemic or for other reasons.
Most importantly, to my knowledge, most are “natural” athletes who take nothing stronger than protein powder and pre-workout. I did not ask about the use of PEDs (performance enhancing drugs) though. These are just regular guys who lift on a regular basis. It’s intended to be a random sample of who you might meet in a typical gym and, let’s face it, in today’s culture you are likely comparing yourself to a couple of guys who are juicing but you don’t know it. Okay, I’ve got a couple ringers in my sample group who were once elite athletes and a couple personal trainers who lift for a living.
Let start with the numbers rounded to the nearest quarter inch or half centimeter:
- Average Height – 70 inches (178 cm). Yes, they are a relatively tall group.
Median Height – 70 inches (178 cm). Seven men are 5’10” exactly and make up the most common height. The next most common height it 5’11” (180 cm) with three men this tall.
- Average Arm Unflexed – just under 15 inches (38 cm).
Median Arm Unflexed – 15 inches (38 cm).
- Average Arm Flexed – 16.3 inches (41.4 cm)
Median Arm Flexed – 16.25 inches (41.3 cm)
Average Difference Between Flexed and Unflexed Arm – just under 1.5 inches (3.8 cm). Median difference is 1.5 inches exactly (3.81 cm)
I threw the last measurement between the flexed and unflexed arm in for fun. Remember, when an arm is flexed the volume of the muscle doesn’t change, just the shape of it does. It’s my understanding that the difference in size between a flexed and unflexed arm can be an indication of how much fat is in the arm because you can’t flex fat. This is not true with the very lean man but may be true for those of us with a more substantial BMI. I’ve noticed myself that the leaner I get the greater this difference becomes. My difference is 2 inches (5 cm). The largest difference in the survey was at 2.5 inches (6.5 cm) and the smallest at a half inch (1.3 cm) which oddly enough was on a man who I know is very lean.
So what can we learn from the above information? I think the obvious take away is that if you lift you can expect your arms to get to at least 16 inches (42 cm) at a minimum regardless of height. Interestingly enough the tallest men in my survey, who were both 6’3″ (190.5 cm) did not have the biggest arms. That honor belonged to a man who stands 6’1″ (185.5 cm) with 18.25 inch (46.5.cm) arms. Likewise the shortest man at about 5’5″ (165 cm) had arms an inch larger, at 16″ (41 cm) than men 6 inches taller than him! However, in general, the men over 6 feet tall had larger arms. This probably shouldn’t be a surprise as a bigger skeleton has more room for muscle to grow. Even though overall proportions may make that taller man look leaner at a technically larger size than the shorter guys.
And before you get concerned that a 17 inch arm is too small – go read my blog post on when is a man’s arm considered big that I mentioned earlier. You’ll find out that the average non-lifter’s arms are much smaller. By several inches!
To sum everything up, it’s better to go for an arm that looks big than one which is actually big. Especially if you happen to be under 6 feet tall. Any man who is sporting a muscular arm that measures 16″ (41 cm) or more can consider his arms to be big. And likely, so will everyone else!
Stay lean, focus on the triceps as much if not more than the biceps, and you’ll be getting second looks because of the size of your “guns” soon enough. Tall guys, the good news is that you can likely build arms which exceed those of a man who is shorter. But, bad news, if you are like most of the tall men I know at least, you’re going to have to keep pushing on to 18″ (46 cm) to look really big. And remember, the true 18″ arm is rare.
If you need some tips on building big biceps check out another one of my blog posts The Secret to Building Big Arms Which No One Else is Willing to Share.
Well, what are you waiting for? Stop flexing in the mirror and go get lifting!
P.S. – do you want to participate in this survey? It’s not too late. Just comment or message me with your stats and I’ll add them into the sample group.
P.S.S. – want to know how your chest stacks up? Go to When is a Man’s Chest Considered Big.
All photos by David P. Wahr unless otherwise noted in which case the original artist retains all rights. Otherwise photos and words @copyright by David P. Wahr