Can you guess the natural hair color of these 20 celebrities?

It’s been a long time since Canadian chanteuse Celine Dion embraced her chestnut-colored roots, but back when she was still a promising young vocalist, the brand ambassador for L’Oréal Paris used to rock her natural wavy brown curls for all to see.

While Amy Adams is one of the most famous redheads in Hollywood, she was actually born a blonde. In TimesTalks from the New York Times, she said, “Based on the roles I was getting called in for, people were responding to certain types of characters with me as a blonde and the minute I went red, it was quirky and fun instead of flirtatious and dumb.”

That's right, Angie wasn't born with the hair color we're all accustomed to seeing, nor is her hair the same shade of blond she had in films like Girl Interrupted or Gone in 60 Seconds. Her natural hair color is more of light chestnut brown with dirty blonde highlights.

A high ponytail, and very straight locks. That’s what comes to mind when we think of the Thank U, Next singer. We also think of all the times she’s dyed her hair light brown, silver, and even lavender. But all those shades are far from the original: a very dark mane of hair full of cascading curls.

Bella Thorne has dyed her hair every color of the rainbow. Even before Disney's Shake It Up we would've assumed she was a natural redhead. But the childhood photo on the right shows us that her real hair color is in fact blond.

Charlize Theron looks fabulous as a platinum blonde, but that’s not her natural hue. The South African actress has a much darker color with ash brown streaks and some natural highlights.

We're used to seeing Chrissy Teigen with warm sand-colored blond highlights in her hair, light chestnut brown, or other summery colors. But her real hair color is actually much darker, as you can see in one of the photos that she posted online from her early days as a cheerleader.

Emma Roberts has also experimented with different hair colors, like her aunt Julia, but her natural color is brown. As you can see in the photo on the right, as a child she used to have darker hair with sun-kissed golden highlights.

A California dirty blond shade has characterized Jennifer Aniston for so long, but if we look back to the first seasons of Friends we'll see her showing off light brown tresses with golden highlights.

We've seen Jennifer Lopez with honey highlights, and we’ve even seen her in very blond shades before. But do you remember back when she starred in Selena? With so many hair color changes over the course of her career, we’ve forgotten that Jenny from the Block’s hair is naturally dark brown.

Jessica Alba's long tresses have a caramel-colored brown shade now, and in the past we've also seen her showing off a dirty or ombré blond color. Her real hair color, however, is a dark chocolate brown.

We all remember Julia Roberts with long red hair from My Best Friend’s Wedding and Pretty Woman, and in recent years we’ve seen her with dark-rooted loose blond curls; the truth is, though, that her natural color is chestnut brown.

Can you remember Karlie Kloss having any other hair color than blond? If you have a look through some of her photos from the distant past, you'll see that she’s a natural brunette.

Actress Kristen Stewart has gone from wearing her hair long to cropped short just as easily as she's gone from blond to brunette. Her natural hair is actually strawberry blond, as you can see during her child star days.

Ever since Leighton Meester starred as Blair in Gossip Girl she's slowly started to lighten the color of her hair, which is allowing her to get closer to her natural color, which is actually blond! The co-creator of the TV series, Josh Schwartz, told The Hollywood Reporter that they required her to dye her hair light brown when she had the audition.

Throughout her career, Miley Cyrus has run the gamut on hair styles and colors; while her days of sporting blond and ombré tones are her most memorable to date, these colors are far from the caramel-colored brown that she was born with.

Perhaps today we're used to seeing Nicole Kidman as a platinum or strawberry blond, but that wasn't always the case. When she began her Hollywood career, the Australian actress had a red head full of curls. “My hair isn't easy to manage,” she told People in 1989.

We'll always think of Reese Witherspoon as legally blonde —although she has been known to use darker brown shades before— but the fact is that her natural color is dark blond with golden highlights.

Over the course of her career, Scarlett Johansson has had hair colors ranging from the shade of red worn by the Black Widow to the golden blond that we’ve come to associate her with. However, as she grew up in the spotlight, we can remember back when her hair was naturally light brown with beachy natural highlights.

No, Sofía Vergara’s natural color is not what you've gotten used to seeing over the years. “I'm a natural blonde. But when I started acting, I would go to auditions and they didn't know where to put me because I was voluptuous and had an accent - but I had blonde hair,” she told Self in 2010.