Melanoma is the most dangerous of skin cancers, and now a new tool claims to help people over 40 calculate their risk of developing it in the next 3.5 years.

Created by researchers at Australia's QIMR Berghofer Medical Research Institute, the online risk predictor works with accumulated data from 42,000 people aged between 40 to 70 years of age in the world's largest study of skin cancer.

The tool's results are determined from a person's age, sex, ability to tan, number of moles at age 21, number of skin lesions treated, hair colour and sunscreen use. From there, the tool will classify you as one of five risk groups, from very much below average to very much above average.

It makes sense the tool was developed in Australia — the country has one of the highest rates of melanoma in the world, and it is Australia's third most common cancer.

"This online risk predictor will help identify those people with the highest likelihood of developing melanoma so that they and their doctors can decide how to best manage their risk," lead researcher Professor David Whiteman said in a statement.

Although there have been other melanoma risk calculators, the researchers say these were based on different study designs and are less accurate. The effectiveness of QIMR's melanoma prediction tool have been published in the Journal of the National Cancer Institute.

"We have tested our online risk predictor thoroughly and found that it is accurate at predicting a person’s risk of developing melanoma," Whiteman added.

"Nonetheless, people should be aware that the tool provides only an estimate of future risk and it is not a substitute for getting their skin checked by a doctor.

"We encourage people to use it as a general guide, and if it says you have a high risk of melanoma, we strongly encourage you to visit your doctor and discuss whether a skin check would benefit you."

Remember to stay safe in the sun, silly.