Background: A previous study has confirmed the feasibility of one-item question scales to adequately measure current anxiety in a female-only sample in clinical settings. This study aims to further determine whether a one-question likert scale can be used in measuring anxiety in the general population for both genders. Method: A convenience sample of adults, recruited via a smartphone application (app) published freely in Apple’s app store that have completed the Social Phobia Inventory (SPIN) questionnaire and a one-item anxiety question scale. Result: 1,233 participants from the US, UK, Australia, and Canada completed the questionnaire. 67% of participants were female, with a high school education level, and a relatively young age, while the participants’ mean age was 28.7. Chi-square analysis has shown no significant differences between countries, in terms of gender χ2 (3, N = 1233) = 4.5 p = .21, education level χ2 (9, N = 1233) = 14.5 p = .10, and age F(3,1232) = 1.52, p = .21. There was a strong, positive, partial correlation between SPIN score and the one-question anxiety scale, controlling for age, gender, country, and education, r = .72, p < .001, with a high SPIN score being associated with a higher score on the one-question anxiety scale. An inspection of the zero order correlation (r =.73) suggested that age, gender, country, and education had very little effect on the strength of the relationship between SPIN score and the one-question anxiety scale. Conclusion: This study confirmed that the one-question anxiety scale is suitable to be used to measure anxiety in both genders.