With over 3.5 billion fans worldwide, football ("soccer") is the most popular sport on the planet. It always ranks at the top of the majority of the credible lists published.
Usually, popularity is measured based on the "number of viewers/fans". According to a website called mostpopularsports.net, here are the top 3:
Football (which is equivalent to American soccer) is the most popular overall
Tennis is the most popular "individual" sport (no team required)
Golf is the most popular "solo" sport (can be played alone).
Additional opinions from WikiAnswers sports fans:
"Most popular" could mean "most watched," "most played," or "most revenue-generating." Based on the variable definition of "most popular" the following observations apply:
The most played sport, not just watched, in the world is also football (American Soccer).
Based on the number and size of stadiums around the world, the number of people who wear football (American Soccer) merchandise, the number of people who are aware of football, and the number of leagues/tournaments worldwide (The World Cup, UEFA Champions League, The South American Cup, The American Cup, The Asian Cup, 70 English league teams, 40 Italian league teams, 40 Spanish league teams) football ranks at the top of the list regardless of the definition of "most popular."
Rugby is very popular in many former English colonies (with the notable exception of the US) and has a large following. However, participation rates fall below that of football.
Manchester United is the most popular sports team and the biggest sport franchise on the planet. It has over 450 million fans all around the world. Its estimated value is $1.9 billion in value, which well exceeds that of the Dallas Cowboys and Real Madrid.
Most Frequently Cited Ranked Lists
1) Football: 3.3-3.5 billion fans (Europe, Africa, Asia, Americas, etc.)
2) Cricket: 2-3 billion fans (India, UK, Pakistan, Asia, Australia, etc.)
3) Field hockey: 2-2.2 billion fans (Asia, Europe, Africa, Australia)
4) Tennis: Around 1 billion fans (Europe, Americas, Asia)
5) Volleyball: Around 900 million fans (Asia, Europe, Americas, Australia)
6) Table tennis: Around 900 million fans (Asia, Europe, Africa, Americas)
7) Baseball: Around 500 million fans (US, Japan, Cuba, Dominican Republic)
8) Golf: Around 400 million fans (US, Canada, Europe)
9) Gridiron (American football): 390-410 million fans (US mainly)
10) Basketball: Not more than 400 million fans (US, Canada mainly)
Another list from sportingo.com/answers.com/Wikipedia
1. Soccer (association football, also known as futbol in various Spanish-speaking countries)
2. Cricket
3. Rugby
4. Field Hockey
T5: Baseball
T5: Basketball
Christ folks, use google for god's sake.
In every credible top 10 list football/soccer is number one by usually a wide margin.
An estimated 3.5 billion fans worldwide as opposed to 400 million basketball fans.
Here's facebook's take...
The world’s five most popular things / people / phenomena on Facebook at the time of writing are Texas Hold’em poker (almost 22m fans), followed by Michael Jackson, Facebook itself, Lady GaGa and the TV show Family Guy.
Cristiano Ronaldo, at No16 in the overall rankings of the most popular things in the world, is only slightly less popular than South Park, and slightly more popular than music.
Messi is slightly less popular than Jackie Chan, and slightly more popular than basketball.
Federer is slightly less popular than the Turkish football team Galatasaray, and slightly more popular than CSI.
Bryant is slightly less popular than the iPod, and slightly more popular than the Jonas Brothers.
Michael Jordan is slightly less popular than dancing, and slightly more popular than Starburst (formerly Opal Fruits).
Beckham is slightly less popular than Starburst, and slightly more popular than the character Alan from the movie The Hangover.
Nadal is slightly less popular than Johnny Depp, and slightly more popular than MTV.
Phelps is slightly less popular than Radiohead, and slightly more popular than Enrique Iglesias.

























