Purpose: The aim of this study was to evaluate the readability and the quality of toothache-related information found in Brazilian websites. Materials and Methods: Fifty-five websites retrieved from Google Search, Baidu, Yahoo! and Bing were evaluated by two independent examiners using the DISCERN questionnaire, the Journal of American Medical Association (JAMA) benchmark criteria and the Flesch Reading Ease adapted to Brazilian Portuguese (FRE-BP). Additionally, the websites were categorised according to their information, adopting four criteria related to: (i) endodontic pain, (ii) toothache relief or treatment, (iii) the self-resolution of pain, and (iv) the promotion of home remedies usage. The statistical analysis was performed using Spearman's rank correlation coefficient, Mann–Whitney U test, hierarchical clustering analysis by Ward's minimum variance method, Kruskal–Wallis test, post-hoc Dunn's test and Chisquare test. P 0.05 was considered statistically significant. Results: The overall means (± SD) of DISCERN and FRE-BP were, respectively, 31.02 (± 5.56) and 61.20 (± 11.79), without quality-based differences between the websites with health- and non-health-related authors, and distinct clusters. Conclusion: Therefore, the quality of toothache-related information found in this sample of Brazilian websites was classified as simple, accessible and of poor quality, which can hamper the personal decision-making process of seeking dental treatment, leading to damages caused by the non-effective self-management of toothache. Keywords: toothache, eHealth, medical informatics, consumer health information