One of the determining factors of the quality of Web search engines is the size of their index. In our ISSI 2015 paper, we present the results of a longitudinal analysis of estimating the size of Google and Bing’s indexes over a nine-year period. This is the companion Web page for this ISSI 2015 paper.

This is the companion Web page for our work on estimating search index sizes.

  • Recent daily estimates of search engine index size can be accessed on WorldWideWebSize.com
  • Full data of our longitudinal analysis
  • A complete, color-coded, numbered list of all reported infrastructure changes is available here. Changes shown in bold correspond to the changes highlighted in our paper.

If you want to use this data, please cite one of the following publications:

  • A. Van den Bosch, T. Bogers, and M. de Kunder, “Estimating Search Engine Index Size Variability: A 9-Year Longitudinal Study,” Scientometrics, p. 1–18, 2016.
    [Bibtex]
    @article{Van-den-Bosch:2016,
    author = {Van den Bosch, Antal and Bogers, Toine and de Kunder, Maurice},
    title = {{Estimating Search Engine Index Size Variability: A 9-Year Longitudinal Study}},
    journal = {Scientometrics},
    year = {2016},
    pages = {1--18},
    month = feb
    }
  • A. Van den Bosch, T. Bogers, and M. De Kunder, “A longitudinal analysis of search engine index size,” in Proceedings of the 15th international conference on scientometrics and informetrics, A. A. Salah, Y. Tonta, A. A. A. Salah, C. R. Sugimoto, and U. Al, Eds., ISSI society, 2015.
    [Bibtex]
    @InCollection{Van-den-Bosch:2015,
    author = {Van den Bosch, Antal and
    Bogers, Toine and
    De Kunder, Maurice},
    editor = {Albert Ali Salah and
    Yasar Tonta and
    Alkim Almila Akdag Salah and
    Cassidy R. Sugimoto and
    Umut Al},
    title = {A Longitudinal Analysis of Search Engine Index Size},
    booktitle = {Proceedings of the 15th International Conference on Scientometrics
    and Informetrics},
    publisher = {{ISSI} Society},
    year = {2015},
    }