In many parts of the world, shadow education has become a major enterprise. Such is the case of the countries of the former Eastern Bloc, including the Czech Republic, which is in scope of this article. The study analyses the Internet supply of private tutoring lessons in academic subjects and assesses the micro- and macro-factors influencing the offered lesson price as set by private tutors. Based on the quantitative content analysis of 2058 individual tutor profiles advertising online, the author found a very unequal distribution of tutors within the country and a considerable proportion of mainstream schoolteachers acting as private lesson providers. The higher the formal education and age of the tutor, the higher the price they offer per lesson. Male tutors set higher prices than female tutors, and tutoring in foreign languages is generally more expensive than in any other subject. The results suggest that the features of private tutoring supply have implications for equity in education.