The Online Gambling Disorder Questionnaire (OGD‑Q) was developed to assess online gambling disorder in adolescents. Currently, there is no questionnaire for measuring online gambling disorder among adults. The aim of this study was to evaluate if the OGD-Q would also be suitable for use in adults. Survey responses from 937 adults aged 18 to 64 years were examined. Participants completed the English version of the OGD-Q. The researchers found that all items of the OGD-Q loaded onto one factor reflecting the severity of online gambling problems. This was consistent with previous research with adolescents. The results showed that the OGD-Q was a reliable and valid measure for use among adults. Furthermore, scores on the OGD-Q could be meaningfully compared across subgroups of adults, including between men and women, and between emerging adults and older adults.