The D21 Digital Index is the result of an annual survey of 20,500 Germans aged 14 and over. The survey is based on a battery of 200 questions organized around four themes. These four themes are used to create a sub-index, which measures the progress of each of the four themes on a scale of 100 each year.

• Access: use of the Internet at work and in a private setting, use of broadband, equipment, Internet connectivity of devices used
• Diversity and intensity of use: digital applications used on a regular basis, average duration of internet use
• Digital skills: knowledge of digital subjects, skills related to uses
• Openness: acceptance and interest in innovation, benefits and relevance of the Internet, fears and concerns

These four sub-indices are aggregated in an index, the D21 Digital Index, which measures each year, on a scale of 100, the "digital development of the society".

The results of the 2013, 2014, and 2015 surveys were somewhat disappointing: they recorded, year after year, a near-stagnation of the index around 51 (out of 100).

The 2016, 2017, and 2018 surveys, on the other hand, had recorded an overall increase in the index, reaching 55 points in 2018.

With 58 points in 2019, the D21 Digital Index records a three-point increase.

86% of the population has access to digital technology: this is increasing in all age groups, especially among the older generations. The proportion of people without digital access is now around 14%.

A simplified typology of the German population, in three categories, "digital pioneers"(Digitale Vorreiter), "digital followers"(Digital Mithaltende, those who cope) and "digital outcasts"(Digital Abseitsstehende, those who are out of the game) summarizes the direction of the developments.

In 2019, the "digital pioneers" category would have grown by 7 points, according to the survey results.

The weighting of the four families of indicators that make up the D21 Digital Index is as follows: digital skills account for 40%, access for 30%, openness for 20%, and uses (diversity and intensity) for 10%. sub-indices, including the 14-year summary, the indicators of "digital development of the digital society.

The D21 Index is jointly funded by the Federal Ministry of Economic Affairs and Energy and several large companies.