Welcome to FRAX®

The FRAX® tool has been developed to evaluate fracture risk of patients. It is based on individual patient models that integrate the risks associated with clinical risk factors as well as bone mineral density (BMD) at the femoral neck.

Dr. John A Kanis

Dr. John A Kanis
Professor Emeritus, University of Sheffield

The FRAX® models have been developed from studying population-based cohorts from Europe, North America, Asia and Australia. In their most sophisticated form, the FRAX® tool is computer-driven and is available on this site. Several simplified paper versions, based on the number of risk factors are also available, and can be downloaded for office use.

The FRAX® algorithms give the 10-year probability of fracture. The output is a 10-year probability of hip fracture and the 10-year probability of a major osteoporotic fracture (clinical spine, forearm, hip or shoulder fracture).


The FRAX tool is designed to assist clinicians in predicting the ten-year probability of fracture with or without the addition of femoral neck bone mineral density (BMD). It is freely available and is used for around 2.8 million fracture calculations per year. The tool has been independently evaluated to be effective and robust, and has been approved by the National Institute for Health and Care Excellence in the UK and the Food and Drug Administration in the USA.

The University of Sheffield launched the FRAX tool in 2008. At that time the University hosted the The World Health Organisation (WHO) Collaborating Centre for Metabolic Bone Diseases (1991-2010), and the FRAX tool is based on data generated from that centre. However, FRAX was neither developed or endorsed by WHO . The University accepts that any references to the ‘WHO tool’ or to the WHO Collaborating Centre after it finished its work in 2010 are incorrect. We regret these mistakes and we are working to correct them wherever they appear.

FRAX Desktop Application

Click here to view the applications available

Web Version 3.11

View Release Notes


FRAX available as iPhone App

View in iTunes
Individuals with fracture risk assessed since 1st June 2011