I always have a hard time with standard size hats. I am always paranoid that they won't fit or will be to short or long or tight. If you have not yet noticed, when it comes to my projects, I am SUCH a perfectionist. I know I have a ton to learn and always try and expand my skills in everything I do. But I still can't help but worry. Frequently.
I looked up websites that have to do with hat sizing and I found this one with a simple chart that shows average head circumferences. So now I feel much more comfortable starting new patterns and being able to accurately gauge out my sizes!