Kristen Stewart (AP file photo)

HOLLYWOOD -- That real date on their birth certificates isn't the only thing celebs tend to guard with their lives.

They also happen to be fairly sensitive where other vital stats are concerned, like actual height, weight and waist measurements.

And that's just the guys.

But there are no secrets where a film or TV production's wardrobe department is concerned, and, thanks to our trusty studio insider, Deep Thread, we've got the low-down on all the taking up and letting out.

If your girlfriends tell you you're the spitting image of the Twilight saga's Kristen Stewart, then that means, in addition to those stunning green eyes, you stand 5-foot-5 in bare feet, weigh 105 pounds, have a 33-inch bust, a 25-inch waist, 33-inch hips and a 0-2 dress size.

At least that's how she shapes up for her latest film production, The Runaways, a biopic about the groundbreaking '70s teen grrrl rock outfit, in which she plays the part of Joan Jett.

By contrast, Michael Shannon who plays the part of the band's controlling manager, Kim Fowley (he was also the only entertaining part of Revolutionary Road), is a big guy. He stands about 6-foot-3,

wears a 44-46L jacket, has a 171/2-inch neck, and a 39-inch waist and a 33-inch inseam.

Over on the set of Men of a Certain Age, the new Ray Romano dramedy series, they were recently seeking photo doubles for fellow cast members Andre Braugher (an even 6-feet with a 46L jacket and a 17/34 shirt) and Matthew Modine (6-foot-4 with a 46L jacket and a 17/35 shirt).

On the same show you've also got regulars Penelope Ann Miller (5-foot-6 with a 4-6 dress size) and Lisa Gay Hamilton (5-foot-2 and a size 2).

Meanwhile, on the Eastwick set, there's Canada's own Paul Gross cavorting with all those witchy women as he fills the role of Daryl Van Horne, played by none other than Jack Nicholson in the 1987 film.

Where Jack stood a couple of hairs under 5-foot-10, Gross tops off at 5-foot-11, weighs about 175 pounds, wears a 42L coat, a 161/2/36 shirt and 36/33 pants.

Always saw yourself as more a character type than leading man material?

Then you might be interested in knowing that Kevin James, who traded in his Paul Blart garb for a Big Chill-style ensemble outfit called Grown Ups, is 5-foot-9, admits to weighing 275 pounds and wears a 51-53 coat size.

In comparison, Michael Chiklis comes by his The Thing brawn honestly.

The tough-guy actor, who plays a no-nonsense principal in the upcoming comedy, High School, may be just 5-foot-81/2 but he's got a 171/2 neck, a 34 sleeve and wears a size 46S jacket.

And if you're just an average-sized, middle-aged balding guy, you'd probably be more in the Hector Elizondo range, as in 5-foot-10, 40R jacket, 16/34 shirt and 33/32 pants with a size 10 shoe.

Director Garry Marshall's good luck charm, Elizondo will soon be seen in Marshall's Valentine's Day, an all-star rom-com featuring Julia Roberts, Bradley Cooper, Anne Hathaway and Jamie Foxx.

See? In Hollywood, even ordinary guys get love, too.