List of 100 Grand International number-one songs of 2009

The 100 Grand International is a chart that ranks the best-performing international songs in Valstrath. Its data, published by The Grand magazine and compiled by Tiescon SoundScan, is based collectively on each song's weekly physical and digital sales, as well as the amount of airplay received on Valstrathian radio stations and streaming on online digital music outlets.
During 2009, sixteen singles reached number one on the 100 Grand. In total, fifteen acts topped the chart as either lead or featured artists, with seven—Lady Gaga, Colby O'Donis, Kid Cudi, Kings Of Leon, Arctic Monkeys, Owl City and Alicia Keys—achieving their first 100 Grand number-one single.
The longest running number one song of the year was "21 Guns" by Green Day, that led the charts for a total of seven weeks, the song also topped the Year-End 100 Grand.
Lady Gaga, Beyoncé and Kings of Leon were the only acts to have multiple number one singles this year, with three for Lady Gaga and two for the other ones.
== Chart History ==
The bold song represents the song of the year.
Issue Date 	Song 	Artist
January 3 	"Single Ladies (Put A Ring On It)"	Beyoncé
January 10 	"Single Ladies (Put A Ring On It)"	Beyoncé
January 17 	"Just Dance" 	Lady Gaga ft. Colby O'Donis
January 24 	"Just Dance" 	Lady Gaga ft. Colby O'Donis
January 31 	"Just Dance" 	Lady Gaga ft. Colby O'Donis
February 7 	"Just Dance" 	Lady Gaga ft. Colby O'Donis
February 14 	"Day 'n' Nite" 	Kid Cudi
February 21 	"You're Gonna Go Far, Kid" 	The Offspring
February 28 	"You're Gonna Go Far, Kid" 	The Offspring
March 7 	"You're Gonna Go Far, Kid" 	The Offspring
March 14 	"You're Gonna Go Far, Kid" 	The Offspring
March 21 	"You're Gonna Go Far, Kid" 	The Offspring
March 28 	"Sex On Fire" 	Kings of Leon
April 4 	"Sex On Fire" 	Kings of Leon
April 11 	"Poker Face" 	Lady Gaga
April 18 	"Poker Face" 	Lady Gaga
April 25 	"Halo" 	Beyoncé
May 2 	"Halo" 	Beyoncé
May 9 	"Halo" 	Beyoncé
May 16 	"Halo" 	Beyoncé
May 23 	"Halo" 	Beyoncé
May 30 	"If Today Was Your Last Day" 	Nickelback
June 6 	"If Today Was Your Last Day" 	Nickelback
June 13 	"If Today Was Your Last Day" 	Nickelback
June 20 	"Use Somebody" 	Kings of Leon
June 27 	"New Divide" 	Linkin Park
July 4 	"New Divide" 	Linkin Park
July 11 	"New Divide" 	Linkin Park
July 18 	"21 Guns" 	Green Day
July 25 	"21 Guns" 	Green Day
August 1 	"21 Guns" 	Green Day
August 8 	"21 Guns" 	Green Day
August 15 	"21 Guns" 	Green Day
August 22 	"21 Guns" 	Green Day
August 29 	"21 Guns" 	Green Day
September 5 	"I Gotta Feeling" 	The Black Eyed Peas
September 12	"I Gotta Feeling" 	The Black Eyed Peas
September 19	"If U Seek Amy" 	Britney Spears
September 26	"If U Seek Amy" 	Britney Spears
October 3 	"Crying Lightning" 	Arctic Monkeys
October 10 	"Paparazzi" 	Lady Gaga
October 17 	"Paparazzi" 	Lady Gaga
October 24 	"The Fixer" 	Pearl Jam
October 31 	"The Fixer" 	Pearl Jam
November 7 	"The Fixer" 	Pearl Jam
November 14 	"Fireflies" 	Owl City
November 21 	"Fireflies" 	Owl City
November 28 	"Fireflies" 	Owl City
December 5 	"Fireflies" 	Owl City
December 12 	"Empire State Of Mind" 	Jay-Z & Alicia Keys
December 19 	"Empire State Of Mind" 	Jay-Z & Alicia Keys
December 26 	"Empire State Of Mind" 	Jay-Z & Alicia Keys
==Extra Info==
* Lady Gaga scored her three first number one singles with "Just Dance", "Poker Face" and "Paparazzi".
* "Halo" topped the charts for 5 weeks and stayed in the top 10 for 23 weeks, resulting in the song becoming the second most played international song of valstrath in 2009.
* Kid Cudi scored his first number one single with "Day 'n' Nite"
* Green Day's comeback single "21 Guns" debuted at number one and topped the charts for 7 consecutive weeks, which led to the song become song of the year.
* Jay-Z scored his fourth top 10 single, but first number one single with "Empire State Of Mind", a song with Alicia Keys.
=== Year End Top 10 ===
# 	Song 	Artist 	Peak And Duration
1 	"21 Guns" 	Green Day 	#1 for 7 weeks
2 	"Halo" 	Beyoncé 	#1 for 5 weeks
3 	"You're Gonna Go Far, Kid" 	The Offspring 	#1 for 5 weeks
4 	"Just Dance" 	Lady Gaga ft. Colby O'Donis	#1 for 4 weeks
5 	"New Divide" 	Linkin Park 	#1 for 3 weeks
6 	"The Fixer" 	Pearl Jam 	#1 for 3 weeks
7 	"Fireflies" 	Owl City 	#1 for 6 weeks
8 	"If Today Was Your Last Day" 	Nickelback 	#1 for 3 weeks
9 	"Day N' Nite" 	Kid Cudi 	#1 for 1 week
10	"Single Ladies (Put A Ring On It)"	Beyoncé 	#1 for 2 weeks (in 2009 - 3 total)