Interpretation and description of findings detected in upper-endoscopy and colonoscopy are qualitative processes which depend on the experience and skills of the endoscopist performing the procedure. This explains the high variability of endoscopic reports, hampering their interpretation, specially by general practitioners. Classifications, scores and scales give a quantitative support to these qualitative processes. The aim of this review is to describe the classifications, scores and scales most frequently reported in digestive endoscopy, specially those with the highest methodological support in terms of validation and reproducibility. These tools facilitate the description of findings related to gastroesophageal reflux, Barrett's esophagus, gastroesophageal varices, stigmas related to non-variceal gastrointestinal bleeding, advanced and incipient neoplasms, bowel preparation for colonoscopy and severity scores of inflammatory bowel diseases. In summary, these tools enable to standardize endoscopic reports, simplifying their interpretation.