How to lose your hair in 10 days.

Matthew McConaughey played bathroom barber by giving son Livingston, 10, a haircut at home — and the choppy ‘do is dividing the actor’s fans.

In an Instagram photo posted Sunday by McConaughey’s wife, Camila Alves, the 53-year-old “Interstellar” star is seen wielding a pair of scissors as Livingston side-eyes his dad and brother Levi, 14, monitors his work.

“Then his happened…,” Alves, 41, playfully captioned the snap.

Commenters had a field day with Livingston’s choppy mane makeover.

“Stop it. Seriously, have a professional take care of it!” a concerned fan warned.

“Why o why – Matthew has many talents – but I guess haircuts isn’t one of them,” another bemoaned.

Wrote a third, “Oh noooo! Not the dreaded ‘dad haircut’!!!!”

“Sorry that’s terrible,” a fourth chimed in, while a fifth called the DIY cut “not bad” but added, “don’t quit your day job.”

But not everyone was left dazed and confused by McConaughey’s handiwork; jewelry designer Kendra Scott (who also hails from the actor’s native Texas) approved, writing, “We can add hairstylist to Matthew’s résumé! Liv’s expression is so funny!”

Wrote another fan, “There is nothing that Matthew isn’t great at!!”

In addition to sons Levi and Livingston, McConaughey and Alves also share daughter Vida, 13. It’s unclear who else in the family’s been subjected to one of dad’s DIY trims.