Left-handedness
Will they be a lefty?
About 10% of people are left-handed. The genetic component is real but small — handedness is also influenced by the baby’s position in the womb and prenatal hormones.
Mom's dominant hand
Dad's dominant hand
Chance of being left-handed
9.5%vs. 10% baseline
Most outcomes are typical — and lefties have always done just fine.
Compared to baseline
For your baby9.5%
Average baby10.0%
How accurate is this, honestly?about~10% baseline
Accuracy~10% baseline
Handedness doesn't reliably emerge until age 3-4. Don't try to push a baby toward right-handedness with feeding or play — they'll figure it out. Lefties are slightly overrepresented among artists, athletes, and US presidents, for whatever that's worth.
Read the full methodology →