9 Day-Glo Celeb 'Dos To Inspire You This Summer

Manic Panic isn't just for rebellious teenagers anymore. Dying your hair a shocking hue isn't new (hello, '90s nostalgia), but the practice has become much more mainstream over the last couple of years. After all, when Lauren Conrad is rocking dip-dye extensions, crazy colors are no longer a Sinead O'Rebellion move.

Now that temperatures are heating up, celebs are going next level with their hair, debuting bolder shades than ever before. Some ladies like Lady Gaga and Kylie Jenner have wigs to thank for their ever-changing Muppet manes, but we're here to salute those celebs who are damaging their strands in the name of day-glo dye. Here are our nine favorite neon hues for this summer:

1. Kesha

She’s tested out unicorn highlights and pulled a Kelly Osbourne with lilac locks, but Kesha’s latest look is the boldest we’ve ever seen on her -- which is saying a lot for a singer known for songs with titles like "Crazy Kids" and "We R Who We R" and used to cover her body in neon paint. This new chartreuse shade shines brighter than the sun (and a Mountain Dew bottle), which means it will be nearly impossible to lose this Nashville native in a crowd.

WATCH: Is This the Hottest Hilary Duff's Ever Looked?

2. Hilary Duff

It's hard to shake that good girl Lizzie McGuire image out of our heads, but the one-time Disney queen is all grown up and momentarily ditching her blonde locks and seeing teal. "I've never done anything like this!" she told Ellen DeGeneres in March. "I was just in Cabo with my son, and I was staring at the ocean, and I was like I want that on my head. So this happened." She loved the colorful trend so much, she followed her bluesy turn with pink extensions:

Watch Hilary rock whip those blue locks back and forth in the fan-demanded Tinder-less version of the music video for her new song "Sparks":

3. Nicole Richie

The longtime blonde has been experimenting with bold hair for a while now. While we dig the purple and blue strands she’s had in the past, the bright pink shade she debuted at The Daily Front Row Fashion Los Angeles Awards is perfect for summer and brightens the Candidly Nicole star's complexion.

WATCH: Ellen DeGeneres Inspired Nicole Richie's New 'Do

4. Gwen Stefani

Along with Cyndi Lauper and Pink, No Doubt's main gal was one of the first to sport bright pink hair back in the '90s. Gwen has stuck to a nearly white shade of blond since, save for this fall when she added orange and black to her long bangs. The feather-like extensions were a fun way to add a pop of color to the singer's usually one-hued mane.

5. Katy Perry

The "Dark Horse" singer is the queen of rainbow-colored hair -- after all, it's rare that she sticks to one shade for more than, oh, a week. Our favorite of her more recent looks was a wavy lilac bob she sported at this year's GRAMMYs, but she's gone neon recently too. Last fall, she chanelled The Muppets' Animal with a fiery red-orange shade. What color will she pull off tomorrow? That’s anybody's guess!

6. Lily Allen

The British singer's trademark dark bangs are a thing of the past -- for now. Lily has run the gamet experimenting with colors, and she rarely sports just one shade at a time. In fact, her most memorable Crayola-esque look was red, blue and purple, and she's also gone pink, yellow, lavender and teal. Now, she's rocking watermelon hair that's something to "smile" about. "Not long till I'm 30, one last hurrah on the hair front," she wrote on Instagram. Pardon us, Lily, but we don't quote believe this'll be the last fun look we see on you!

WATCH: Kaley Cuoco-Sweeting Dyes Hair Pink

7. Madonna

As the 56-year-old singer said herself in an Instagram post, "Shut up jealous bitches! I hope you are as fun loving and adventurous as me when you're my age!!!!" Madonna is basically the living embodiment of a mic drop -- and proof that pink hair don’t care at any age.

8. Amber Rose

Even super short cuts can get a bold new style! Amber Rose added a neon blue shade to her normally bleached buzz cut in early April. She went right back to blonde shortly after, which is just proof that that even a temp wash can do the trick if you just want to dip your toes in the crazy color waters.

9. Hayley Williams

The Paramore frontwoman is no stranger to non-traditional hues. We're not sure what her natural hair color is, as Hayley has sported a wide variety of bold, fiery hues for years. After experimenting with yellows and reds, and even a brief but bright turquoise shade, the recently engaged singer is back to her favorite hue -- orange. Our favorite look of hers, however, will always be this half-pink look she sported back in 2013:

Ain't it fun?

If these gorgeous gals don't encourage you to experiment with your hair for the sake of a good photo op, than we don't know who will.

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