Surprise! The Most Popular Baby Names in the US Are ...

Five week old sleeping boy and girl fraternal twin newborn babies.
Parents are always on the lookout for something new when it comes to baby names, says one baby-name expert. (Image credit: Katrina Elena | Shuttterstock)

For the first time in the 21st century, the most popular baby name for boys in the United States is Noah, according to information released today (May 9) by the U.S. Social Security Administration.

Sophia kept its No. 1 slot from last year as the most popular girl name, and Emma moved into the No. 2 spot. Noah was followed by Liam as the second-most popular boy's name of 2013.

"In baby-name terms, that's huge news," said Laura Wattenberg, founder of the baby-name website, referring to Noah's rise to fame. But the fact that Noah and last year's No. 1 boy's name, Jacob, have gotten top marks may not have anything to do with their biblical roots. [See List of 25 Most Popular Baby Names]

"I think it does mark a change in style, even though those are two classical Old Testament names," Wattenberg told Live Science. Rather, she thinks these name choices have a lot to do with sound.

"Noah and Liam are two examples of a style I've called 'raindrop names' — miniature, multisyllable names with a perfectly smooth sound, so there are no hard edges, no stop," said Wattenberg, author of "The Baby Name Wizard: A Magical Method for Finding the Perfect Name for Your Baby" (Three Rivers Press, 2013).

And Sophia, well, that name is "a crowd-pleaser right now," Wattenberg said. Not only is it classical and sophisticated, but it's also cute. And perhaps even more important is that Sophia has the long "o" sound, which, along with all long-vowel sounds, is "very hot this year," Wattenberg said. [Sophia's Secret: Tales of the Most Popular Baby Names]

The top 10 names for girls in 2013 were: 

  1. Sophia
  2. Emma
  3. Olivia
  4. Isabella
  5. Ava
  6. Mia
  7. Emily
  8. Abigail
  9. Madison
  10. Elizabeth

The top 10 names for boys in 2012 were:

  1. Noah
  2. Liam
  3. Jacob
  4. Mason
  5. William
  6. Ethan
  7. Michael
  8. Alexander
  9. Jayden
  10. Daniel

Rise and fall

While they may not have made the top 10, there were some interesting fast risers this year. The two fastest-rising boys' names, Wattenberg said, are Jayceon (often pronounced "Jason") and Jase. The first may have gotten its spark from rapper "Game," whose given name is Jayceon, Wattenberg said. And Jase is the name of one of the brothers on the hit A&E reality TV show "Duck Dynasty." Both names sound like Jason, which, along with their celeb roots, likely gave them the push to soar quickly in popularity.

The two fastest-rising girls' names are Daleyza, the name of the daughter of Mexican singer Larry Fernandez, and Sadie, which was originally a nickname for Sarah. (Sadie is also a star on "Duck Dynasty.")

The fastest-falling baby name, Wattenberg found, is Justin, which was one of those names that sounded so "young." "It has been the cute teenage boy name, but age is finally getting to it, and Justin Bieber seeming less cute to people these days have made 'Justin' the fastest-falling boys' name this year," Wattenberg said.

Unique names

Noah and Sophia may be the most common U.S. baby names, but don't expect your kids' classrooms to be filled with children with those monikers. In general, parents are choosing more unique baby names these days. For instance, researchby Jean Twenge of San Diego State University revealed that about 40 percent of boys were donned with one of the 10 most popular names in the 1880s, compared with less than 10 percent today; that number for girls fell from 25 percent with a top-10 name in 1945 to 8 percent in 2007. (That research was detailed in the January 2010 issue of the journal Social Psychological and Personality Science.)

Whether you should expect to be surrounded by Noahs and Sophias also depends on where you live. Names also vary regionally, with some U.S. states towing the baby-name line while others stray a little farther from traditional naming. For instance, a 2011 study detailed in in the journal Psychological Science showed that Hawaiians are the least likely to choose a top 10 most popular baby name for their kids, while baby boys born in New Hampshire and gals born in Maine are the most likely to be called by a common name. That study found that overall, babies born in newer, so-called frontier U.S. states have more distinctive names compared with their counterparts in older regions such as New England.

As for what inspires this diverse array of baby names today, take your pick: movies, celebrities, days of the week (think Sunday Rose born to Nicole Kidman and Keith Urban), video games and even guns. The search for unique names seems to be driving the current rise in gun-related names, with more parents these days donning their boys with names like Gunner and Colt, while names like Beretta and Kimber are being given to baby girls.

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Jeanna Bryner
Live Science Editor-in-Chief

Jeanna served as editor-in-chief of Live Science. Previously, she was an assistant editor at Scholastic's Science World magazine. Jeanna has an English degree from Salisbury University, a master's degree in biogeochemistry and environmental sciences from the University of Maryland, and a graduate science journalism degree from New York University. She has worked as a biologist in Florida, where she monitored wetlands and did field surveys for endangered species. She also received an ocean sciences journalism fellowship from Woods Hole Oceanographic Institution.