The article analyzes the A. Krymskyi’s codification works in the context of the linguistic heritage of Ukrainian linguists of the late XIX – early XX centuries. The formation of Ukrainian educational institutions prompted linguists to create educational language codes. And the school was a testing area for newly created prescriptions. Theoretical and practical problems of formation of literary standard in connection with tendencies of prescriptive norm are actualized, bases of scientific proof in grammar of historical antiquity, originality of phonetic, lexical and morphological systems of Ukrainian language, evidence of its own way of formation, dialectal variety and scales of functioning are clarified. The source base of codification codes were the language of writers, ethnographic sources, journalistic practice in the projection on the living vernacular. Tendencies of normalization depended on socio-political conditions, the need to justify the status of the Ukrainian language, bringing it to a new cultural level and manifested themselves in the activation of their own internal language resources, fixation of lexical-semantic, grammatical, functional perfection. This statement was indisputable due to the united normative activity of many other linguists, who laid the theoretical foundations for the establishment of the literary norm of the Ukrainian language in all spheres of public life. Issues of Ukrainian rule-making were raised in the late XIX – early XX centuries intensified intralinguistic potential, helped to find acceptable for the whole Ukrainian space literary samples, outlined trends in language development, encouraged future generations of linguists to solve theoretical and practical problems that have not lost their relevance today.