Mustaches. They are polarizing and they can change a wearer's look drastically and dramatically, for better or for worse.

Some celebs look better with 'em than without, while others, like Justin Bieber, try desperately to grow some upper lip pubes but just can't get it going beyond a few errant hairs.

Then there's female celebs who like to play with fake 'staches. They can get away with it and not compromise their femininity since they're clearly faux and applied to their faces in goofy, silly fashion.

We've rounded up some of our favorite mustaches, both real and fake. We left off the milk mustaches, since those aren't made of hair. We had to draw the line somewhere.

Lady Gaga aping Salvador Dali while topless.

Madonna needs a shave.

Da Biebs trying really hard to pull of a 'stache. (He's failing miserably!)

Biebs trying...still!

Kardashians x Jenners celebrating some event with faux 'staches.

Kris Jenner -- mustachioed momager.

Do Kim's cookies count? We know how that sounds...

Brad Pitt rocking a creepy, thin 'stache.

Kiyoshi Ota, Getty Images

Baby-faced Ashton Kutcher's 'stache was grown for Movember.

YouTube

Ricky Martin wearing a 'stache for a role.

Pacific Coast News

Yes, that's actually Zac Efron. He's too pretty for a 'stache.

Pacific Coast News

Normally hunky Matthew McConaughey owns that porno 'stache.

Pacific Coast News

Ewan McGregor is nearly unrecognizable pairing a thick 'stache with a soul patch.

Pacific Coast News

McLovin can grow facial hair?! He's doing a better job than The Biebs.

Pacific Coast News

The flawless Ryan Gosling pulls this off.

Jason Kempin, Getty Images

James Franco...is up for anything, even bad face pubes!

Kevin Winter, Getty Images

That heartthrob Bradley Cooper does scruffy! He dirties down (as opposed to cleans up) nicely.

Stephen Lovekin, Getty Images