How do you know if you have big arms?

You can determine if you have big arms by measuring the circumference of your biceps and comparing it to average sizes for your height and build. Additionally, if your arms appear muscular and well-defined, and you receive compliments or notice that they stand out in clothing, these are good indicators. Regular strength training can also contribute to arm size, so consider how much you lift and your workout routine. Ultimately, personal perception and comparison with others can also play a role in your assessment.