Are you worth 12 cows?

"You're not a size six, and you're not good looking. Well, you'd better be rich, or be real good at cooking," sings Lily Allen on her hit Hard Out Here.

She might well have been talking about the launch of Lobola Calculator, a new app that calculates the lobolo worth of a woman who doesn't know it herself - based on responses to questions about her physical attributes, education and marital history.

The app, developed by Johannesburg techno boffin Robert Matsaneng, is available from the Android app store and is being developed for iOS and BlackBerry.

The app first asks for your age, height, weight and waist size, then asks you to honestly rank how attractive you are between "not at all" and "really hot". It then asks for your highest qualification, and if you are employed, previously married or have children.

For a 25-year-old woman who is 1.65m tall, weighs 55kg, wears size 32 pants, considers herself "really hot", has a matric, is employed (no specifics required ) and has children (number not required), the prospects look surprisingly bleak. She is worth a paltry R5000 and no cows at all. But if the same woman has no children or previous marriages, she is worth R40000 and five cows.

Matsaneng, 26, said he developed the app because "my friends are getting married and I don't want them to be ripped off".

But he was quick to stress that the app was "pure entertainment".

He said he had tested it on "many" women.

@m_kittykat tweeted: "So, according to this Lobola Calculator I'm worth R60500. Baby needs to start saving up."

The average lobolo in Eastern Cape is R85000 or 15 cows, R35000 or five cows in Western Cape and Mpumalanga, R85000 or 11 cows in Limpopo, R30000 or five cows in Northern Cape, R65000 or eight cows in North West, R82500 or 12 cows in Gauteng, and R78000 or 10 cows in KwaZulu-Natal.