This paper deals with the complementarity of Google's tools used for digital advertising - Google Ads, Search Engine Optimization (SEO), Google Analytics, and their features. The development of digital marketing has led to the development of tools used in digital advertising to achieve sales, with Google tools being a very important component of digital marketing. The analysis of the complementarity of Google tools is valuable because of the potentially more successful results that these tools can bring regarding the increase of sales. The methods used in this paper include a detailed study and processing of the available literature, a multidisciplinary approach, and the research of the advantages and disadvantages of individual tools. The circumstances in which Google's digital advertising tools can be used as a combination of tools, that is, the potential for complementarity of three previously mentioned Google tools, has been determined. The results of the research showed in which circumstances a particular tool would be more effective, and in which circumstances the most effective option would be to use these tools together as part of a digital marketing business strategy. The optimal combination could be the use of Google Ads as a way of advertising, the use of SEO services offered by external companies, and the use of Google Analytics tools to collect and analyse the data about the users we draw into the website. In short, there is the possibility of complementing Google Ads, SEO, and Google Analytics tools in order to improve marketing activity.