By now, everyone knows Bozoma Saint John.

The former Apple exec — who's now in charge of branding at Uber — first made a splash on stage at WWDC in a hot pink dress last year. Since then, her style choices have been equally eye-catching, unexpected, and often stunningly beautiful, making Saint John an obvious choice for the No. 1 slot.

What makes Saint John the best dressed exec in Silicon Valley is the fact that she doesn't actually dress like she works in the Valley at all. Her outfits are bold and fashion-forward, and often have a nod to her Ghanaian roots through accessories like jewelry and bags.

As a young, female exec in a male-dominated industry, Saint John could easily feel pressured to tone it down and cover up, but she doesn't. While her peers are ensconced in oversized hoodies and poorly fitting jeans, Saint John will show up in a skin-tight leather cat suit or a pink plunging mini-dress. She always seems to stay true to herself and her personal style instead of trying to fit in, and will hopefully encourage more women in the Valley to use fashion to express themselves.

- Barbour essential gilet, $149

- Garrett Leight Van Buren folding sunglasses, $365

Jeff Bezos wouldn't have been at the top of this list a few years ago, but he's recently undergone a style transformation.

These days, Bezos can be seen in high-end sunglasses, slim-fit suits, tight t-shirts and polos, and cool outwear like vests and bomber jackets. While most people suspect he's adopted a new workout regimen, he also appears to have taken an interest in how his clothes look and feel. Bezos is now the richest person in the world and these days, he actually looks the part.

- Armani Collezioni lurex tweed zip-front jacket, $417

- Vince Camuto Armaceli over the knee boot, $119

Arianna Huffington is one of the most fashionably dressed CEOs in tech, and likely in business as a whole. Her choices are creative, on-trend, and almost always a little surprising.

The best thing about Huffington's style is that she's not afraid of new prints, patterns, and textures. She also plays with silhouettes, pairing full skirts with high boots or skinny pants with pointy-toe slingbacks. Huffington also clearly pays attentions to fit and appears to have a tailor on retainer. If there's a closet worth raiding in tech-land, it's Huffington's.

- Ralph Lauren men's classic-fit neat ultraflex sport coat, $59

- Vince Abe suede sneakers, $160

Brian Chesky got his start at RISD, so it makes sense that he also has an eye for fashion.

The Airbnb CEO frequently wears clothes and shoes from designers like Gucci and switches up standard business-casual outfits by getting creative with fit, color, and texture.

Chesky's shoes in the top photo, for instance, are a mix between sneakers and boots, but they're rendered in gray suede. Rather than a standard button-down shirt under his blazer, he opted for a collar-less version. And even his t-shirts are two-toned.

Another great thing about Chesky's style is that as a former athlete and bodybuilder, he knows his body well and chooses clothes that look great on him.

- Burberry macramé lace trench coat, $2,895

- Burberry buckle detail suede peep-toe ankle boots, $695

Before joining Apple, Angela Ahrendts led Burberry, so it's not much of a surprise that she has a great fashion sense.

From the looks of things, Ahrendts has never encountered a trench coat she didn't love. She has them in varying prints, colors, and materials, and usually pairs them with pants and high-heeled boots. The look really works for her, and helps her stand out in the Silicon Valley boys club.

- Harris Wharf London concealed single-breasted coat, $423

- Missoni ripple-stitch scarf, $155

You'd expect the CEO of IBM to be a conservative dresser, but that's not the case with Ginni Rometty.

Rometty picks chic, beautiful clothing at every occasion, and she manages to look appropriate for the corporate world and extremely stylish at the same time.

Rometty's royal purple coat paired with a patterned scarf while leaving the White House looks bold and stylish, while her leather jacket on stage adds an edge to a simple black dress. Rometty's personal style is a perfect model for female executives in Silicon Valley — and beyond.

- Neiman Marcus cashmere long-sleeve polo sweater, $248

- Salvatore Ferragamo patent leather low-top sneaker, $530

When Satya Nadella first came on board as CEO of Microsoft, he was quickly lauded for his great sense of style.

While Nadella favors a lot of the same types of clothes as his Silicon Valley brethren like hoodies, polo shirts, and jeans, what sets Nadella apart is his eye for detail.

Rather than choosing a boring, basic pair of sneakers, Nadella wears high-end Lanvin shoes. Instead of a boring, basic polo shirt, Nadella usually chooses a shirt made out of a cool textile. Plus, Nadella's clothes are always perfectly fitted, almost like they were made just for him. Other Valley execs should take some notes.

- Everlane cashmere hoodie, $140

- Rick Owens Island Dunk high-top sneakers, $1,115

Jack Dorsey has had one of the most dramatic style evolutions over the past few years, which is why he earns such a high ranking.

When Dorsey first hit the scene, he had long bangs and was prone to wearing button-down shirts tucked into jeans. These days, it's a much different story.

While Dorsey's style can veer dangerously into Yeezy Season territory, his affinity for a tougher aesthetic looks much cooler than his mid-2000s style. He's rarely photographed without a leather jacket or Rick Owens shoes, and he tends to choose trendy, stylish formal wear.

- Nordstrom men's shop marled yarn sweater, $79.50

- Lanvin suede and patent-leather sneakers, $495

Instagram CEO Kevin Systrom is arguably the most put-together executive in Silicon Valley.

Systrom has rallied against sloppy dressing and has argued that people who make beautiful products shouldn't be considered "indulgent" for also caring about how they dress. He always looks the part of a CEO, and he seems like someone who wouldn't be caught dead in sweats.

Systrom, like several of his Silicon Valley peers, opts for pricey sneakers and slim-fit jeans most of the time. If I had to put a label on it, I'd define Systrom's style as "nerd chic," but that's not insult — his buttoned-up, preppy aesthetic works for everything from casual outfits to a classic tux.

- Adrianna Papell crepe sheath dress, $50

- Michael Kors Janice boots, $147

It's tough to find a photo of Facebook COO Sheryl Sandberg either very dressed up or very dressed down. She seems to have one mode: Poised and professional.

Sandberg isn't the most daring when it comes to fashion, but she knows what looks great on her and she sticks to it — she's almost always wearing a form-fitting, solid-color sheath dress and knee-high boots or pumps.

While it would be nice to see Sandberg branch out for her uniform, her choices are varied enough that she always keeps it interesting.

- James Perse high gauge jersey tee, $95

- Common Projects Achilles low-top sneakers, $415

Evan Spiegel is no stranger to the fashion world. He's graced the pages of Italian Vogue, talked about his must-haves with GQ, and he's also married to model Miranda Kerr.

Spiegel has a specific personal style and great taste. He favors high-end sneakers and pricey t-shirts, and is on a constant quest "to find the perfect aviator."

But Spiegel loses a few points simply because his choices are boring. He told GQ he's been wearing the same t-shirts and sneakers since high school, and he rarely strays from some combination of black, white, and gray. While Spiegel always looks great in a young, hip, California-kid kind of way, it's time to switch it up now that Snap is a high-profile public company.

- Alexander McQueen velvet and satin blazer, ~$828

- Nike Lunar Flyknit HTM NRG, $425

Elon Musk is a billionaire, thrice-over CEO, serial dater of famous actresses, and the real-life inspiration for Tony Stark. Luckily for him, his style choices just about match that.

While his choices can occasionally veer into "dad" territory, Musk has a sense of style that places him a cut above many of his fellow execs. He looks great in a tux, has one or two killer pieces — like the Alexander McQueen velvet jacket pictured above — and knows when a Tesla graphic tee and Nikes will do the job.

- Emerson Rose leather jacket, $349

- Nine West Argyle boots, $119

As the CEO of YouTube, Susan Wojcicki has one of the coolest jobs at Google — and a wardrobe to match.

Wojcicki's style is pretty straightforward — she tends to choose solid colors and simple styles — but she's always perfectly dressed for each occasion.

Her cropped leather jacket and ankle boots at Google I/O helped her stand out as one of the few women on stage, and knee-high boots at the Fortune conference helped make an otherwise standard shift dress a bit more interesting.

- The Kooples contrast yoke track jacket, $425

- Lanvin suede and patent leather low-top sneakers, $495

Google CEO Sundar Pichai falls into a similar category as Cook: Serviceable, but not exciting.

What sets Pichai apart is his preference for track jackets and zip-up sweaters. He's photographed wearing one at most public appearances — including several recent Google keynotes — and usually pairs them with jeans and pricey sneakers.

Pichai's style choices tend to be more interesting that his contemporaries, and certainly better than his boss, Alphabet CEO Larry Page.

- Bonobos slim fit denim sport shirt, $128

- Nike Roshe One, $75

While Apple CEO Tim Cook at least has more interesting personal style than his predecessor, Steve Jobs, his outfit choices can best be summed up as boring.

There's nothing wrong with how Cook dresses, exactly. His wardrobe mostly consists of jeans, t-shirts, blue shirts, and crewneck sweaters — plus the occasional tuxedo.

But as my colleague Dennis Green pointed out, when Cook does put on a suit, it often doesn't fit him correctly and he usually opts for a boring black-on-black jacket and pants. While Cook always looks put together and professional in a Silicon Valley sense, you'd expect the head of one of the most valuable companies in the world to have better personal style.

- Think Out Loud Apparel acoustic guitar t-shirt, $15.99 (Ek has this exact t-shirt! At least he's a bargain shopper)

- Nike Air Force 1 '07, $90

When it comes to personal style, Daniel Ek gets points for knowing what works for him.

The Spotify CEO has a go-to "look" that he more or less sticks to for most public appearances: jeans, sneakers like Nike Air Force 1s, and a graphic t-shirt, with or without a blazer.

While he's not bringing anything very innovative to the table — in fact, that specific combination peaked in the mid-2000s — he dresses pretty much like you'd expect the head of a music streaming giant to dress.

That said, just like Mark Zuckerberg, it wouldn't kill him to switch it up once in a while.

- Calvin Klein muted stripe polo, $40

- Common Projects original Achilles full-grain leather sneakers, $430

Netflix CEO Reed Hastings isn't a lost cause on the style front, but he certainly doesn't get a gold star.

While he looks OK once in a while, Hastings biggest faux pas is that he's typically wearing one too many shirts. In the middle photo below, he could have done without the visible undershirt, while in the photo above, he's wearing a shirt, sweater, and jacket...indoors.

Where Hastings redeems himself is with his love for Netflix-themed holiday sweaters. He tends to wear them on quarterly earnings calls, making him one of the few tech CEOs with a great sense of humor.

- Belstaff Gaynesford striped sweater, $255

- Clarks Wallabee boot in maple suede, $140 (Ive has these chukka boots in at least two colors)

Apple's design boss, Jony Ive, is regarded as one of the most respected minds in design. He's responsible for the look and feel of every Apple product, including the packaging.

But for someone who designs sleek, stylish, luxurious products, Ive's personal style leaves a lot to be desired.

With the exception of formal wear — he has a quirky penchant for white tie ensembles and throwback looks, like coats with tails — Ive frequently looks rumpled and disheveled. His pants are often too long and his shirts too oversized, or he opts for garish colors like orange jackets and red socks. While Ive gets points for creativity, Apple's design guru could use a stylist.

- Brunello Cucinelli cotton crew neck t-shirt, gray: $295 (Zuckerberg wears the brand, but his tees are special made and reportedly cost between $300 and $400).

- Nike Flyknit Lunar 3, wolf grey: $150

Sorry, Mark.

While the Facebook CEO cleans up nicely at awards ceremonies (pictured above), he's at the bottom of the list due to his insistence on wearing one thing and one thing only: A gray crewneck t-shirt, jeans, and Nike running shoes.

While he's at least had the decency to ditch the hoodie in recent years, it's bordering on the absurd that Zuckerberg can't take five minutes out of his morning to dress himself.

If there's one positive about Zuck's wardrobe choices, it's that his jeans and rare suits or tuxedos are always well-fitted.