Text analysers and CEFR

I will be happy to learn if someone here has used Englishprofile text inspector. It classifies the words in a text according to CEFR level but how can the overall level of the text be estimated on the basis of this classification?

It's probably based on looking to see if certain language features are found in the text- the presence of advanced ways of connecting and sequencing language, for instance. The results suggest that it is comparing the text analysed with word lists associated with each level, so more complex vocabulary, etc, will suggest that the text is of a higher level.

Thank you for answering, but may be you are speaking about the analyser on this website.
Englishprofile text analyser only groups text vocabulary into levels. Actually, even in advanced texts the greatest percentage belongs to A1 vocabulary, and vice versa - simple texts can include a small percentage of C1 vocabulary. It is likely that Englishprofile offers also CEFR level estimation of the whole text upon subscription but I am not sure if it really works that way.

Of course, because advanced texts contain simple language. However, the proportion of more complex language will be higher than a simple text.