OBJECTIVES: The primary aim of this study was to evaluate generalized joint hypermobility (GJH) according to the Beighton scoring system in an Australian population. Secondary aims were to identify whether the commonly used Beighton score cut-off of ⩾4 is appropriate, and to suggest age- and sex-specific Beighton score cut-offs across the lifespan. METHODS: A thousand individuals aged 3-101 years were assessed for GJH with the Beighton scoring system. Differences between age, sex and ethnicity were investigated. The appropriateness of the ⩾4 cut-off was investigated with use of a binary logistic regression. Each Beighton score cut-off was established as the nearest Beighton score that delineated the uppermost 5% of the population. RESULTS: Overall, females and non-Caucasians had higher Beighton scores across the lifespan (P < 0.001). Based on a binary logistic regression model, if a cut-off of ⩾4 was utilized, the Beighton scoring system demonstrated a sensitivity of 0.8% and a specificity of 99.3% (P < 0.001). A cut-off of ⩾4 was only found to be appropriate for females aged 40-59 years and males aged 8-39 years. CONCLUSION: Beighton scores varied across the lifespan and were significantly influenced by age, sex and ethnicity. Assessing GJH using the Beighton scoring system required age- and sex-specific cut-off scores based on the uppermost 5% values. This was confirmed by the low sensitivity, high specificity and 60% false-positive rate if a cut-off of ⩾4 was used for both sexes across the lifespan. To lower the risk of a false-positive diagnosis of GJH, further tests of hypermobility need to be utilized.