What Is the 10/40 Window?

The 10/40 Window is the rectangular region of the Eastern Hemisphere spanning from 10° to 40° north latitude — running from West Africa across the Middle East, through Central and South Asia, and into East Asia. Missiologist Luis Bush first coined the term in 1990 after identifying the concentration of spiritual lostness, poverty, and limited missionary access within this band.

It is not a political boundary or a doctrinal concept. It is a geographic reality: the place on earth where the fewest people have had a meaningful opportunity to hear the message of Jesus Christ.

The 10/40 Window spans North Africa, the Middle East, Central Asia, South Asia, and East Asia.

The window contains some of the world's most populous nations — including China, India, Bangladesh, Pakistan, and Nigeria — along with dozens of smaller countries where open Christian witness carries legal risk, social cost, or both. The regions within it include:

• 🌍 North Africa
• 🕌 The Middle East
• 🏔 Central Asia
• 🌏 South Asia
• 🌐 Southeast Asia
• 🇨🇳 East Asia

Within these regions are thousands of distinct people groups — defined by shared ethnicity, language, and culture — who have no indigenous, self-sustaining church capable of reaching their own people without outside help. These are the unreached.

How Unreached Is Unreached?

The word "unreached" has a specific missiological definition: a people group in which less than 2% of the population is evangelical Christian and there is no indigenous church capable of evangelizing the rest of the group. By that definition, the 10/40 Window contains most of the world's unreached people.

The disproportion is the problem. An estimated 90% of global missionary resources — personnel, funding, infrastructure — flow toward people and places that already have access to the Gospel. The 10/40 Window, which contains the majority of the world's spiritually unreached people, receives less than 10% of those resources.

That gap is not an accident or an oversight. It is partly the result of access barriers — restrictive governments, hostile cultural contexts, physical remoteness. But it is also a resource and prioritization problem. More workers are needed. More funding is needed. And that funding has to come from somewhere.

That is where Sacred Supply Studio's Sacred Mission™ capsule enters. 100% of net profits from the Sacred Mission™ capsule fund missionaries serving the unreached — specifically through our partner, Within Reach Global.

Three Unreached Peoples

The 10/40 Window is not an abstraction. It is made up of specific people with names, languages, histories, and needs. Here are three of the largest unreached people groups living within it — three among thousands.

Population and religious affiliation data drawn from the Joshua Project and International Mission Board databases. Figures represent estimates and are subject to ongoing revision.

Frequently Asked Questions

• Why is it called the "10/40 Window"?

  The name refers to the geographic band between 10° and 40° north latitude in the Eastern Hemisphere. Missionary strategist Luis Bush used the term in 1990 to highlight that this band contained the highest concentration of people with little access to the Gospel, along with the world's highest levels of poverty and the most restrictive governments for religious practice.

• What countries are in the 10/40 Window?

  The window includes countries across North Africa (Morocco, Algeria, Libya, Egypt, Sudan), the Middle East (Saudi Arabia, Iran, Iraq, Syria, Jordan, Turkey), Central Asia (Afghanistan, Pakistan, Uzbekistan, Kazakhstan, Tajikistan), South Asia (India, Bangladesh, Nepal, Bhutan), Southeast Asia (Myanmar, Thailand, Laos, Vietnam, Cambodia), and East Asia (China, North Korea, Japan). Not all parts of every country fall within the 10°–40° band, and missionary access varies significantly by country and region.

• What does "unreached" actually mean?

  A people group is considered "unreached" when less than 2% of its population is evangelical Christian and there is no indigenous church movement capable of spreading the Gospel to the rest of the group without outside cross-cultural missionary support. The threshold is not about individuals who have technically heard something about Christianity — it is about whether there is enough of a Christian presence to sustain ongoing evangelism and discipleship within the group's own culture and language.

• Why don't more missionaries go to the 10/40 Window?

  Multiple barriers combine: restricted access (many countries in the window do not allow traditional missionary work), cultural resistance (deep religious identities in Islamic, Hindu, and Buddhist contexts make open evangelism socially costly), physical danger (some regions carry real risk for foreign workers), and funding shortfalls. Most missionary organizations report that reaching closed or limited-access nations requires significantly more resources per worker than ministry in open countries. The result is a consistent underfunding of the window relative to the size of the need.

• How does buying from Sacred Supply Studio help?

  100% of net profits from the Sacred Mission™ capsule fund missionaries through Within Reach Global — a missionary organization specifically focused on unreached people groups in the 10/40 Window. Every purchase funds field workers, church planting efforts, and gospel access in places where those things do not yet exist. The math is straightforward: more purchases, more funding, more missionaries in the field. See exactly how the numbers work →