NEW YORK • When Ms Renee Bibby has a good hair day, people stop her on the street and tell her that they love her short, curly hair.
On a bad hair day, though, "I look like a dandelion puff", said the 41-year-old graphic designer in Tucson, Arizona.
Over the years, Ms Bibby, who is of mixed-race descent and describes her hair as "coarse, but not black", has spent hundreds of dollars trying products to maximise the good days and minimise the bad.
Six months ago, she found a winner - a custom-made US$25 (S$34.30) conditioner from a start-up called Prose. She does not shampoo her hair.
"The first day I used it, I got out of the shower and the curl was already in my hair," said Ms Bibby, who used to have to work to bring the curl back. "It's probably taken 10 minutes off my routine."
Prose, whose founders include a former L'Oreal vice-president, uses a quiz, artificial-intelligence algorithms and a 6,000 sq ft production space in Brooklyn's Sunset Park neighbourhood to create what it hopes is each customer's ideal product.
It has shipped 110,000 bottles, will reach US$1 million in monthly sales by its first birthday next month, and is one of the biggest and most successful entrants in what has fast become one of the hottest spaces in the beauty industry - customisable hair care.
Last month, Prose announced that it had raised US$18 million in new funding.
Another start-up, the four-year-old Function of Beauty, uses its own quiz and algorithms - along with a Willy Wonkaesque 50,000 sq ft factory of custom-built machines.
It has sold one million bottles, said its chief executive Zahir Dossa, a trained computer scientist from the Massachusetts Institute of Technology. Prices start at US$36 for a 240ml set of shampoo and conditioner.
There is more competition coming.
Schwarzkopf, a global cosmetics giant, is conducting trials of custom products in Japan, with plans to bring them to the United States.
Its system includes a hand-held device with an infrared sensor that can detect the hair's molecular structure and analyse its moisture levels. An in-salon machine that looks like the world's fanciest coffeemaker whips up products in 50 seconds, along with a label printed with a bar code for reordering.
Unlike brands that offer different products for each hair "goal" (say, preserving colour or thickening hair), companies that customise say they can combine ingredients that will fulfil all of one's hair needs in a single shampoo, conditioner or hair mask.
It is probably not surprising that there are sceptics. Dermatologist Maryanne Senna, director of the Hair Academic Innovative Research Unit at Massachusetts General Hospital in Boston, is unconvinced that customisable shampoos and conditioners work much better than standard ones.
"There are some things we very clearly know can be drying, but then there's a lot of stuff they use that has no evidence to back it up," she said. "Whether it's the hair holy grail comes down to perception."