RANKED: The 19 most successful 'American Idol' contestants of all time

Estimated net worth: $1 million

No. of albums: N/A

Grammy awards: N/A

Other projects: Fradiani's single "Beautiful Life" is the FIFA 2015 Women's World Cup Official Anthem. His first album is slated to come out this year.

Estimated net worth: $1 million

No. of albums: 1

Grammy awards: N/A

Other projects: Glover was featured on Chadd Black's 2015 single "Love No Fear." Her next album is due out this year. She is also starring in the gospel musical “The Love Shack,” which opened in LA in February.

Estimated net worth: $1.2 million

No. of albums: 3

Grammy awards: N/A

Other projects: McCreery attends North Carolina State University with a major in communications. He also supports and performs to benefit several charities, including Operation Christmas Child, City of Hope, World Vision, and Major League Baseball's Reviving Baseball in Inner Cities program.

Estimated net worth: $2 million

No. of albums: 2 (one with band Elijah Hooker)

Grammy awards: N/A

Other projects: Johnson is releasing his second solo album this year.

Estimated net worth: $2 million

No. of albums: 3

Grammy awards: 1 nomination, 1 win

Other projects: Hicks guest-starred as the judge of a singing competition (alongside fellow "Idol" alum Clay Aiken) on "Law & Order: SVU." The first "Idol" winner to score a long-term Las Vegas residency, Hicks currently performs at the Paris Las Vegas.

Estimated net worth: $2.5 million

No. of albums: 5

Grammy awards: N/A

Other projects: Allen has cowritten several songs for other artists, including "Before We Come Undone" for South African "Idol" winner Lloyd Cele, "Still Got Tonight" for "Glee's" Matthew Morrison, and "Raise Your Hand" for "The Voice" winner Javier Colon.

Estimated net worth: $3 million

No. of albums: 7

Grammy awards: 1 nomination

Other projects: He competed on the 15th season of "The Biggest Loser." He has also branched out into acting with several guest roles on TV shows, including "8 Simple Rules," "Life on a Stick," "All of Us," and "Eve." And he founded an organization to advance arts in education.

Estimated net worth: $3.5 million

No. of albums: 2

Grammy awards: N/A

Other projects: Phillips supports and performs to benefit several charity organizations, including the Sarah foundation and the Gibson flood relief campaign.

Estimated net worth: $5 million

No. of albums: 4

Grammy awards: N/A

Other projects: In 2009, Cook signed an endorsement deal with Skechers shoes. The proceeds for Cook's song "Permanent" went to researching brain cancer, which his brother died from in 2009.

Estimated net worth: $5 million

No. of albums: 5

Grammy awards: 11 nominations, 1 win

Other projects: She starred in a Lifetime movie about herself, and starred in two Broadway shows, "The Color Purple" and "After Midnight." She also starred in her own reality show for VH1, "Fantasia for Real."

Estimated net worth: $6 million

No. of albums: 4

Grammy awards: N/A

Other projects: McPhee successfully transitioned into an acting career with lead roles on TV shows "Smash" and "Scorpion," and in movies "The House Bunny" and "You May Not Kiss the Bride."

Estimated net worth: $6 million

No. of albums: 9

Grammy awards: N/A

Other projects: Aiken has supported and worked with several charities benefitting children, autism causes, gay rights, HIV/AIDS, and served as a UNICEF ambassador. In 2014, he ran for a congressional seat in North Carolina, but was defeated by the incumbent.

In 2008, he appeared in the Broadway production of "Monty Python's Spamalot." Aiken has also guest-starred on TV shows "The Office," "Law & Order: SVU," and "Drop Dead Diva." He competed in the fifth season of "Celebrity Apprentice," becoming runner-up to winner Arsenio Hall.

Estimated net worth: $8.5 million

No. of albums: 7 (One each with bands Cadence and Absent Element, five with band Daughtry)

Grammy awards: 4 nominations

Other projects: Daughtry broke into television with a guest appearance on "CSI: New York." He was cast on the Fox pilot "Studio City," but the network didn't order it to series. Recently, he appeared on Fox's musical event, "The Passion." He has the third-highest record sales of "Idol" contestants behind Kelly Clarkson and Carrie Underwood.

Estimated net worth: $10 million

No. of albums: 3

Grammy awards: 1 nomination

Other projects: In 2008, Sparks launched her own clothing line at Wet Seal. She also has a fragrance line.

She has appeared on the TV shows "Suite Life on Deck," "Big Time Rush," and "CSI," and on the Lifetime TV movie "Dear Secret Santa." She made her movie debut in "Sparkle," and followed that with "Left Behind: The Movie."

In 2008, she launched the I'm M.A.D. Are You? campaign to urge young people to volunteer in their communities. She also established the Jordin Sparks Experience, which donates its proceeds to several charities.

Estimated net worth: $12 million

No. of albums: 3

Grammy awards: 1 nomination

Other projects: Lambert is an outspoken activist for LGBT rights, honored by GLAAD, PFLAG, and Equality California, among other groups.

On TV, he starred on Fox's "The Rocky Horror Picture Show Event" in 2015, made a cameo as himself on "Pretty Little Liars," and starred in a recurring role on "Glee."

He has also served as the lead vocalist of iconic rock band Queen since 2011.

Estimated net worth: $20 million

No. of albums: 3

Grammy awards: 5 nominations, 1 win

Other projects: Hudson won an Academy Award, a Golden Globe Award, a BAFTA Award, and a Screen Actors Guild Award for the role of Effie in the musical movie “Dreamgirls.” She has also appeared in several other films, including "Sex and the City," "The Secret Life of Bees," "Winnie Mandela," and "Chi-Raq."

On TV, she starred in recurring roles on "Smash" and "Empire," and stars in the upcoming HBO movie "Confirmation."

She cofounded The Hudson-King Foundation for Families of Slain Victims, in honor of her mother, brother, and young nephew who were killed by her sister's estranged husband.

Estimated net worth: $28 million

No. of albums: 7

Grammy awards: 12 nominations, 3 wins

Other projects: Kelly Clarkson created a line of greeting cards with American Greetings, which are sold exclusively at Walmart. She also wrote a children's book titled "River Rose and the Magical Lullaby," to be published by HarperCollins in October 2016. She has had several top 10 hits on the Billboard Hot 100.

Estimated net worth: $70 million

No. of albums: 5

Grammy awards: 13 nominations, 7 wins

Other projects: She has her own line of Nicole by OPI nail polish and fitness wear sold at Dick's Sporting Goods. She also founded animal, community, and arts in school organizations in her hometown, Checotah, Oklahoma. In 2010, the singer launched the Academy of Country Music Lifting Lives Temporary Home Fund to aid Tennessee flood victims in 2010.

Underwood has appeared on the TV show "How I Met Your Mother" and in the film "Soul Surfer." She also earned rave reviews as Maria in NBC's live broadcast of "The Sound of Music."

One of the leading stars of country music, Underwood was inducted into the Grand Ole Opry in 2008 and into the Oklahoma Music Hall of Fame in 2009.