Usability Comparison of Text CAPTCHAs Based on English and Chinese

  • Junnan YuEmail author
  • Xuna Ma
  • Ting HanEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9741)


Text CAPTCHAs are widely deployed in nowadays for websites to defend malicious attacks. Although most text CAPTCHAs employ alphanumeric characters, there are emerging interests in designing CAPTCHAs based on regional languages. Here, we conducted experiments to compare the usability of CAPTCHAs based on English and Chinese. The results indicate that, comparing with CAPTCHAs that employ random English or Chinese characters, those based on frequently-used English or Chinese words provide the best usability in terms of efficiency, effectiveness and satisfactory for participants who are native Chinese speakers while familiar with English. CAPTCHAs based on random Chinese characters, however, is least user-friendly from a comprehensive perspective. The evaluation method and results presented here may shine a light for the design of CAPTCHAs that employ characters other than alphanumeric.


CAPTCHAs Usability Human-computer interaction Cross-culture design 



Junnan Yu gratefully thank Dr. Runze Li for helpful discussion. This work was supported by Shanghai Pujiang Program under Grant No. 13PJC072, Shanghai Philosophy and Social Science Program under Grant No. 2012BCK001, and Shanghai Jiao Tong University Interdisciplinary among Humanity, Social Science and Natural Science Fund under Grant No. 13JCY02.


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  1. 1.School of Media and DesignShanghai Jiao Tong UniversityShanghaiChina

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