18 Singing Celebs: Who Makes the Grade?

It's up to the listener to decide whether ''Jam,'' the first single from the famously curvy reality-TV mini-mogul, really qualifies as a singing debut. While a thumping loop from überproducer The-Dream pounds in the foreground, Kardashian's vocals sound like the Auto-Tune the News guys took a crack at a pre-party voicemail she left for one of her sisters. ''I'm goin' out tonight/It's goin' down, headed straight to the front of the line,'' she informs us in a matter-of-fact verse. The beat shakes and grinds; Kardashian yawns and reapplies her lip gloss. If she wants to join the ranks of real dance divas, Kardashian will need to develop some sonic assets as titillating as her visual ones. D —Adam Markovitz

Everyone's well aware that Gwynnie can adopt a British accent and recommend not-so-cheap places to stay in Florence via GOOP. But it's easy to forget how she surprised us all by going ''Cruisin''' with Huey Lewis in 2000's Duets. And then she took it further with the title track from her recent fallen-Nashville-star drama Country Strong, which made us believe that her twang was natural. B+ —Tim Stack

No one expected much when the infamous celebutant released her first single in 2006, but ''Stars Are Blind'' shocked everyone by being a fun, buoyant beach jam that became a top 10 hit in 18 countries. (The song went to No. 18 in the U.S.) B- (B+ for ?Stars? — our guilty pleasure) —Tanner Stransky

Johansson famously took on a series of Tom Waits songs, but her originals were nearly all Debbie Downers. The sullen single ''Falling Down'' felt more depressing than watching divorce court. B —Brad Wete

''I'm tired of rumors starting /I'm sick of being followed,'' our then-teen queen warbled on 2004's ''Rumors,'' long before her real woes began. The frenetic, but oddly infectious, club banger managed to be certified gold in the U.S., but she never really went anywhere on the charts. C —Tanner Stransky

The Oscar winner's Auto-Tune-assisted hit ''Blame,'' which places all accountability on the liquor you drank rather than the brain you own, packed dance floors for weeks. A- for the Ray Charles stuff, B for Jamie as Jamie. —BW

The Gossip Girl star has a good singing voice, which she proved in a guest vocal on Cobra Starship's party anthem ''Good Girls Go Bad'' and in her role as a country ingénue in 2010's Country Strong. Unfortunately, Meester's solo work so far has mostly buried her breathy vocals underneath club-ready pop production. If she ever stops trying to go Gaga, she could be the rare actress with a legit music career. B —Darren Franich

In her moonlighting hours as a snarling, snazzy-pantsed rock star, Lewis (Cape Fear, Due Date) sweats like Iggy and struts like Suzi Quatro, but despite her commitment to the cause (and general on-stage badassery), the music on her four albums inevitably feels redundant, mimicking the greats who are clearly her inspiration. B- —Leah Greenblatt

It's easy to forget that Ryan Gosling — best known for his parts in boundary-pushing movies like Blue Valentine and Half Nelson — actually got his start as a chirping tween alongside Britney, Justin Timberlake, and Xtina on The Mickey Mouse Club. But songs like ''In the Room Where You Sleep,'' the stormy 2009 single from his band Dead Man's Bones, offers a rewarding blend of Gosling's present and past: the studied voice of a lifelong singer, the alt-folk charm of an indie idol, and the giddy energy of a former kid star who still remembers how to put on a good show. B+ —Adam Markovitz

Gossip Girl's Momsen not only transformed into a badass on the series but also in real life, adding major eyeliner and shunning pants. The transformation is surprisingly effective; Momsen more than pulls off the raspy rock vocals on songs like ''Make Me Wanna Die'' with her band, The Pretty Reckless. B+ —Tim Stack

He earned an Oscar nod for playing an aspiring rapper in 2005's Hustle & Flow. But when it came time for Howard to release his debut album in 2008, the actor's musical taste turned out to be less street than sidewalk café. His first single, ''Sanctuary,'' is a white-tie jazz groove with a dash of sleepy doo-wop, anchored by Howard's mellow rasp. His flow is still scotch-on-the-rocks smooth, but what happened to the hustle? B- —AM

The star of Bored to Death — he's also responsible for the show's titular theme song — is nearly as droll in his music as he is in his acting. At their best, tracks like ''Any Fun'' reveal his gift for sweet McCartney-on-a-lazy-Sunday songcraft. B+ —LG

The last thing we thought we'd see Will Smith's wife become is the lead singer of a metal band (Wicked Wisdom). And now we're just hoping she never does it again. C —BW

Even before she married Death Cab for Cutie frontman Ben Gibbard, Deschanel had already been certified as the kewpie-eyed dream-girl of indie-dom. She & Him, her project with acclaimed singer-songwriter M. Ward, pairs her plaintive warble with sunny Burt Bacharach-esque jangle, to frequently charming retro effect. B+ —Leah Greenblatt

Since 2004, the Good Will Hunting star has been moonlighting as a pensive singer-songwriter who'd be right at home on a Lilith Fair ticket. On her 2004 debut single ''Invisible Girl,'' Driver sounds confident and classy, even if her opaque lyrics (''Panda eyes and your sister's dress that you took and you tore'') aren't exactly sing-along fodder. B —AM

Crowe's music career is a bit of a punchline, but the lead single from his solo album is an overlooked gem. Named for Crowe's aunt who committed suicide, ''Raewyn'' plays out as a multigenerational story song and a surprisingly thoughtful meditation on fatherhood. (Best of all, no 30 Odd Foot of Grunts in sight!) B- —DF

Before his first solo original ''Summer Rain'' hit we'd only seen Morrison in Will-Schuester-of-Glee mode, singing covers of the likes of ''Gold Digger'' and ''One Less Bell to Answer.'' But this debut proved to be quite the letdown; ''Rain'' fell flat as a Jason Mraz-esque ditty with a little bit too much R-rated sexual desire. B for the Broadway career, D for the inane horniness of ''Rain.'' —Tanner Stransky

The actor's long-running rock outfit 30 Seconds to Mars has cemented his status as a serious musician (''serious'' being the operative word; dude does not take himself lightly). The band has now released two EPs and three studio albums of brooding alt catharsis, including 2005's platinum-certified A Beautiful Lie. B —LG