Gender Forecast

Estimate the probability of your next baby's sex following the Science Advances (2024) study. Link

Language

Required data

Enter the birth sequence and a few details about the mother.

Sequence of children already born (example: MFMF)

Use only letters M and F, in the order the children were born.

Mother's age at first birth

Enter age in whole years. If unsure, round up or down.

Include the last birth in the count?

Leave off to ignore the last baby and dampen potential stopping bias.

Prior Alpha (alpha)

Alpha sets baseline male tendency; default 6.67 from sex ratio 1.08.

Prior Beta (beta)

Beta sets baseline female tendency; default 6.18 to keep mean ~0.519.