Purpose: . The main objective of this research was to measure the compliance of the user interfaces of 14 computer science Q&A websites with Nielsen’s Ten Usability Heuristics (1993) and to compare their performance in order to identify design strengths and weaknesses and provide suggestions for improving user experience.

Methodology: The user interfaces of the following websites were reviewed and ranked by 3 evaluators: Stack Overflow, Stack Exchange, Quora, Reddit, Chegg, CodeProject, Coderanch, Google Groups, Super User, Server Fault, Cross Validated, Ask Ubuntu, Software Engineering, and Computer Science. Kolmogorov-Smirnov and Shapiro-Wilk normality tests, along with Kruskal-Wallis and Friedman non-parametric tests, were employed for data analysis using SPSS version 27 software.

Findings: the studied websites generally possess a good level of usability (overall mean score of 3.41 out of 4.00). However, significant differences in website performance were observed. The heuristics “Match Between System and the Real World” and “Recognition Rather Than Recall” (mean score of 3.86) achieved the highest ratings. The user interfaces of CodeProject (10.15), Software Engineering (10), Cross Validated (9.90), Ask Ubuntu, and Stack Overflow (both 9.50) demonstrated the best performancey.

Conclusion: Despite the generally good level of usability, many websites require improvement in key aspects such as error management and the provision of effective user assistance. Successful websites serve as benchmarks for others. It is recommended that designers and developers place greater focus on Nielsen’s usability heuristics, particularly in the areas of error handling and recovery, to provide a more comprehensive and effective user experience.