Billie Eilish's Bad Guy has been named as the best-selling global digital single of 2019.

The US singer-songwriter's hit was released in March last year and has global converted sales of 19.5 million, according to the International Federation of the Phonographic Industry (IFPI).

Bad Guy is the fifth single from Eilish's debut album, When We All Fall Asleep, Where Do We Go?, and beat popular tracks including Old Town Road by Lil Nas X, and Ed Sheeran and Justin Bieber's I Don't Care to the top spot.

The song topped the charts in more than 15 countries and was Spotify's second-most streamed song worldwide last year. It recently won record of the year and song of the year at the Grammy Awards.

The IFPI triumph comes after 18-year-old Eilish topped the UK charts with her song No Time To Die from the forthcoming James Bond film of the same name.

She became only the second artist to hit number one in the UK with a Bond song, and she was also the first woman and the youngest artist to do so.

IFPI chief executive Frances Moore said: "Billie Eilish has taken the world by storm with her incredible voice and genre-defying sound.

"She is also an artist who addresses important issues like mental health in her lyrics that clearly resonate with her fans all over the world.

"We wish her success for what will no doubt be another standout year."

US rapper Lil Nas X is in second place on the global list of best-selling singles with his breakout hit Old Town Road, which shifted 18.4 million in sales in 2019.

Camila Cabello and Shawn Mendes are in third place with Senorita, which clocked-up 16.1 million sales.

Other artists who have scored singles in the top 10 include Ariana Grande, Lewis Capaldi and Lady Gaga with Bradley Cooper.

Eilish was named the fourth best-selling recording artist of 2019 by IFPI earlier this month, with Taylor Swift taking the top spot.

The top 10 global digital singles 2019 (Source - IFPI)
1. Billie Eilish - Bad Guy
2. Lil Nas X - Old Town Road
3. Camila Cabello and Shawn Mendes - Senorita
4. Post Malone and SwaeLee - Sunflower

5. Ariana Grande - 7 Rings
6. Tones and I - Dance Monkey
7. Ed Sheeran and Justin Bieber - I Don't Care
8. Lady Gaga and Bradley Cooper - Shallow
9. Lewis Capaldi - Someone You Loved
10. Halsey - Without Me

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