Advertising on digital channels constitutes a significant instrument for businesses seeking to drive sales, particularly on e-commerce platforms. The study utilizes a quantitative matrix model to ascertain the most effective advertising channels for an online monobrand cosmetics store, with particular attention to key performance indicators (KPIs) such as: The following metrics are of particular relevance: conversion rate, cost per conversion, and return on ad spent. The matrix's conclusion is that Google demonstrated superior performance in two out of the three key performance indicators (KPIs) and should therefore be regarded as a significant channel for e-commerce purchases. The practical contribution of the paper is twofold. Firstly, it encourages businesses and marketers to use the findings and adjust their media advertising budgets towards the most effective channel for selling objectives. This is especially important if the advertising budgets are rather limited. In the contemporary landscape, social media has emerged as a predominant communication platform. Consequently, marketers and businesses must adopt a multifaceted advertising model that incorporates this channel into their marketing strategy. This approach enables marketers to engage consumers at every stage of the consumer decision journey, thereby enhancing the effectiveness of their marketing efforts.