I’m a grad student in my externship year for speech pathology and have actually just completed quite a few stuttering evals recently, and do fluency therapy on a weekly basis. I don’t stutter myself and I’m not licensed yet so take what I say with a grain of salt. At least in the field, the only way to gauge a standard for severity (ie come up with an “official” rating of mild/moderate/severe) is through standardized norm-referenced assessments like the Stuttering Severity Instrument 4 or even the OASES. The former looks at how often disfluency occurs in comparison to the average population via speaking samples (so probably what you’re referring to), and the latter comes up with a score for how stuttering impacts a person’s quality of life, especially across different settings or speaking situations. Clinically, both should really be taken into consideration for how severe a presentation truly is. **Think of it this way:** Maybe your stuttering is really “severe” but you only really stutter when speaking on the phone, or giving presentations, or talking to an authority figure, or at school or work, or whatever. Is that more or less severe than a person with a more “mild” case of stuttering who stutters in all settings with all kinds of speaking partners? What about a “severe” case where the person isn’t really bothered by it vs a “mild” case that causes the person extreme emotional distress and social isolation? That’s going to be any SLP’s perspective and interpretation, anyway. Aside from testing instruments like that, the rest is all kind of conjecture and comparing it to past experiences working with other people who stutter and going “yeah, this seems like it’s probably on the milder end compared to what I’ve seen in the past” or “wow this person always seems to be struggling with every other syllable no matter the circumstance”. When you go in for speech therapy for the first time you should be getting evaluated with those standardized assessments, and whatever score and severity rating shows up there is typically what goes in the write-up/eval report. (Side note: don’t worry too much if you have an exceptionally good or bad fluency day on the day of testing because data will be collected every session and therapy is structured around your individual needs. Most people vary from day to day anyways and we know that). But beyond all the labels, at the end of the day it’s a pretty useless descriptor as far as treatment goes. As my client if YOU think your stuttering is mild or severe or whatever, I’m going to defer to you on that. It’s okay to use whatever classification fits your experience colloquially.