Aim: This study introduces a novel CT scan-based classification system for the frontal recess to guide Otolaryngologists in assessing surgical approach, case complexity, required surgeon experience, drill necessity, and anticipated operative duration for a frontal sinus dissection. This system specifically evaluates anatomical features of the frontal beak and frontal ostium. Methodology: A retrospective analysis of 826 high-resolution parasagittal CT images of the frontal sinus was conducted. Key anatomical structures, including the frontal beak (FB) thickness as well as the frontal ostium (FO) width were measured. The FB thickness was divided into three categories based on the interquartile range. The FO was divided into two categories based on the ease of instrumentation and the interquartile range, with a narrow FO making the sinusotomy more difficult and hence a greater risk of injury to the posterior table. Results: The FB is graded as 1 (≤6mm), 2 (>6-<9mm) or 3 (≥9mm) and the FO as A (≥5mm) or B (<5mm) with a frontal recess classification (FRC) 1A representing the simplest frontal recess to dissect and FRC 3B the most complex. This system demonstrated high inter-rater reliability, with a Kendall’s W coefficient of >0.95 at p<0.05, suggesting robust clinical utility. Conclusion: We describe a novel grading system for the frontal sinus that is evidence-based, objective, quantifiable, clinically relevant, and easy to use. The system allows rapid, consistent assessment and communication of operative difficulty, required surgeon skill level, operative time, the need for a drill, the extent of drilling and the need for image guidance.