In recent years, determining the most effective time to post on Instagram for increased engagement has become a central concern for digital marketers. Despite its significance, research on this topic remains limited. This study adopts an exploratory research approach to analyze Instagram posts from selected Western countries (Europe and America) and Iranian businesses. The data were collected during the period from February 21, 2022, to March 21, 2022, employing web scraping tools. Classification algorithms, including XGBoost, K-NN, SVM, and Linear Regression, are employed for modeling, with results favoring the XGBoost method for accuracy. The study reveals optimal posting times between 12 and 3 pm for Western Countries businesses and 9 and 12 am for Iranian businesses. Furthermore, it suggests Sunday as the best day for posting in the West, contrasting with Thursday in Iran. In summary, this research underscores the differing ideal posting times in Iran and the West, emphasizing the challenge of constructing a uniform model for all countries.
