The impact of subtitle speed on viewers: a mixed-methods eye-tracking study on Chinese interlingual subtitling

Subtitled audiovisual content is being consumed more than ever, and the increase in subtitle speeds has generated debates about what counts as a comfortable speed for viewers. In China, subtitling has a long tradition with a standard speed of about 5 characters per second (cps), whereas international platforms such as Netflix adopt a faster rate of 9 cps. Yet, little is known about how such rapid speeds affect the viewing experience. This study examines the impact of subtitle speed on Chinese viewers by testing 31 participants who watched English-language videos subtitled into Chinese at both 5 and 9 cps. Using a mixed-methods design, we assessed comprehension, recall, cognitive load, enjoyment, satisfaction, reading behaviour, perceptions and preferences. Results show that whereas faster subtitles did not negatively affect comprehension, they resulted in impaired recall, higher cognitive load, lower enjoyment and worse satisfaction. Eye-tracking further revealed shorter dwell time and fewer revisits at 9 cps, limiting viewers’ ability to finish reading or re-reading subtitles and possibly reducing processing depth. These findings highlight that Chinese viewers benefited from the slower display time of 5 cps subtitles and provide empirical evidence to inform future subtitling standards and practices, with implications for enhancing the viewing experience.