Since 2003 the Thesaurus has been available not only in the printed version but also in electronic form: at first on CD‑ROM and now on-line, under the auspices of the publishers De Gruyter. Many research institutions provide free access to their users. The online Thesaurus includes all the fascicles which have appeared since 1900, not in the form of a simple PDF but in a version which allows the user to look at the structure of articles in depth. While it is possible to find a lemma and read through the article line by line, as in the printed version, one can also use search functions, not available in the printed version, for example to find particular quotations wherever they are in the dictionary, or restrict the search to certain parts of the article, such as the preface, and much more besides (cf. the Userguide).
All source-identifications appear on a blue background so as to stand out prominently. By clicking here one sees the relevant entry in the Index, where abbreviations are expanded and further information on author and work is given. Cross-references also have a blue background, by clicking on which the user is directed straight to the passage referred to. For a clearer presentation of the structure of articles, larger spaces are marked in yellow. To the left of the main text the volume, page and line numbers are given; these correspond exactly with the numbers in the printed version. By a reverse procedure one can enter the page and line numbers and go straight to the desired passage.
As well as the normal view of articles, familiar from the printed page, there are two other ways of looking at an entry, that is, by quotations and by structure:
In this mode, all passages quoted in the article are arranged in alphabetical order in the form of an Index locorum, so that one can find out quickly if a particular passage or author is cited.
The outline view displays the arrangement of an article. By clicking on the plus or minus sign you can open or close the different levels and arrive quickly at the part of the article you are interested in. This is especially useful in articles where the main section is not preceded by a table of contents.