Christianity Today - General Statistics and Facts of Christianity

Christianity is ranked the largest religion in the world today. According to the Pew Forum on Religion and Public Life, in 2010 there were 2.18 billion Christians around the world, nearly a third of the global population.
Pew Forum on Religion and Public Life (2010)

US adherents - 247 million in 2010
UK adherents - 45 million in 2010
Gordon-Conwell Theological Seminary

32% of the world's population is considered to be Christian.
Pew Forum on Religion and Public Life (2010)

US - 246,780,000 (79.5% of the Population)
Brazil - 175,770,000 (90.2% of the Population)
Mexico - 107,780,000 (95% of the Population)
Pew Forum on Religion and Public Life (2010)

According to the Center for the Study of Global Christianity (CSGC) at Gordon-Conwell Theological Seminary, there are approximately 41,000 Christian denominations and organizations in the world. This statistic takes into consideration cultural distinctions of denominations in different countries, so there is overlapping of many denominations.
Center for the Study of Global Christianity (2011)

Major Christian Traditions:

Roman Catholic - The Roman Catholic Church denomination is the largest Christian group in the world today with more than a billion followers constituting about half of the world's Christian population.
Protestant - There are approximately 800 million Protestants in the world.
Orthodox - Approximately 260 million people worldwide are Orthodox Christians.
Pew Forum on Religion and Public Life (2011)

Today in the U.S., about 79.5% of adults (247 million) identify themselves as Christian. In comparison, the next largest religions in America are Judaism and Islam. Combined they represent less than three percent of the United States population.
Pew Forum on Religion and Public Life (2011)
World Religion Database

However, there are more than 1500 different Christian faith groups in North America.
ReligiousTolerance.org

Of the approximate 2 billion Christians in the world today, 279 million (12.8% of the world's Christian population) identify themselves as Pentecostals, 304 million (14%) are Charismatics, and 285 million (13.1%) are Evangelicals, or Bible believing Christians. (These three categories are not mutually exclusive.)
Pew Forum on Religion and Public Life (2011)

In the unevangelized world, there are 20,500 full-time Christian workers and 10,200 foreign missionaries.

In the evangelized non-Christian world, there are 1.31 million full-time Christian workers.

In the Christian world, there are 306,000 foreign missionaries to other Christian lands. Also, 4.19 million full-time Christian workers (95%) work within the Christian world.
Frontier Harvest Ministries

Approximately 78.5 million Bibles are distributed globally per year.
Gordon-Conwell Theological Seminary (2010)

There are approximately 6 million books about Christianity in print today.
Gordon-Conwell Theological Seminary (2006)

An average of 159,960 Christians worldwide are martyred for their faith per year.
Gordon-Conwell Theological Seminary (2010)

More Statistics of Christianity Today:

• Gordon-Conwell Theological Seminary
• ReligiousTolerance.org
• ReligionFacts.com
• Harvest Frontier Missions
• Adherents.com