Melbourne: A new formula predicts the time for love and marriage.

Brainchild of Australian statisticians, the equation works on how old you are when you start looking for a life partner, and the absolute oldest you want to be to tie the knot, reports website.

"Applying maths to matters of the heart is always a dangerous prospect. In human life when you're dealing with emotions you have to think much harder," University of NSW School of Mathematics and Statistics professor Tony Dooley said. "But if you want to work out the right moment to start getting serious, this actually gives you a mathematical framework to think about it."

The university's statisticians claim a success rate of almost 40 per cent.

"Romance by the numbers

1 Choose the oldest age by which you want to get married, for example, 39. Call this ''n''.

2 Decide the earliest age at which you'll start to consider a potential spouse, for example, 20. This age becomes ''p''.

3 Subtract ''p'' from ''n'' (39 - 20), then multiply the result by 0.368. This equals 6.992.

4 Add this to your minimum age.

Result: 27 is your optimal proposal age."