The term “decline of religion” is increasingly discussed in society. But what is the actual situation? According to the Religious Yearbook published annually by the Agency for Cultural Affairs, Japan’s “number of believers” has remained around 170 million, a figure that far exceeds the total population. On the other hand, surveys of individuals show that only about 30% say they have a clear faith.
A “number of believers” that exceeds the population, and a “faith level” that remains low and stable. What does this seemingly contradictory set of statistics mean?
Source: Agency for Cultural Affairs, "Religious Statistics Survey"
The Agency for Cultural Affairs’ Religious Yearbook compiles reports submitted by religious corporations nationwide to their supervising authorities, based on Article 25 of the Religious Corporations Act. The items required for reporting include “number of believers,” “number of clergy and staff,” and “overview of assets,” all of which are administrative information related to the management and operation of the corporation.
The criteria for calculating the number of believers differ by denomination. Some count “registered members on the rolls,” others calculate by “family units,” and in some cases even “include those who were once affiliated.” For example, in temples with the danka (parishioner) system, families who have moved to another prefecture or households with little ongoing connection to the temple may still remain recorded as parishioners in the registry. Similarly, in parishioner or believer registers, unless updates are filed, institutional “affiliation” continues to be maintained.
Thus, the “number of believers” in the Religious Yearbook is not an indicator of the strength of individual faith or participation in religious activities, but rather a tally of “institutional affiliates” reported by religious corporations. These figures function as administrative data to grasp the scale and distribution of religious corporations, but they do not directly reflect the actual state of faith among Japanese people.
Surveys of individuals reveal very different numbers. According to NHK Broadcasting Culture Research Institute’s Survey on Japanese Consciousness (2018), 32% answered that they “do not believe in anything religious,” while the remaining 68% reported believing in some religious object such as gods, Buddhas, or the afterlife (multiple answers allowed). However, only 31% said they “believe in gods,” and 38% said they “believe in Buddhas,” showing that faith in specific objects is limited.
The share of respondents who answered "I do not believe in anything related to religion or faith" is 32%. The remaining 68% said they believe in some kind of religious object such as gods, Buddhas, the afterlife, etc.
Source: NHK Broadcasting Culture Research Institute, "Japanese Value Survey" (2018)
Because multiple answers were allowed, the total exceeds 100%. Many respondents believe in more than one object of faith at the same time, which reflects the layered nature of religious belief in Japan.
Source: NHK Broadcasting Culture Research Institute, "Japanese Value Survey" (2018)
In the Agency for Cultural Affairs statistics, 139% of the population is counted as “believers,” while in individual surveys 68% report having “some kind of faith.” The reason for this gap lies in the difference in what each measures.
Source: Agency for Cultural Affairs(ACA), "Religious Statistics Survey" (2024) / NHK Broadcasting Culture Research Institute, "Japanese Value Survey" (2018)
The Agency’s statistics measure “institutional affiliation with religious corporations,” while individual surveys measure “personal faith consciousness.” Even if institutional affiliation is maintained, individuals may not necessarily have clear faith. This structural difference is the core of the paradox.
Is this gap a temporary phenomenon? Let us look at long-term trends.
NHK survey: NHK has conducted the survey roughly every five years from 1973 to 2018. The share of people who answered "I believe in God" has remained stable at around 30%.
Pew survey: Pew Research Center conducted its survey in 2023. The share of respondents who answered that religion is important in their lives (Very important + Somewhat important) was 38.2%. Although the questions differ from NHK's, the figures similarly indicate a relatively low level of religiosity.
Source: NHK Broadcasting Culture Research Institute, "Japanese Value Survey" (1973–2018) / Pew Research Center, "Religion and Spirituality in East Asian Societies" (2023)
According to NHK surveys, the proportion of people who answered “I believe in gods” has remained stable at around 30% for 45 years, from 33% in 1973 to 31% in 2018. A survey conducted by the Pew Research Center in 2023 also found that 38.2% answered that “religion is important,” showing a similar level.
Individual faith consciousness has remained flat, and the Agency’s “number of believers” has also remained flat. Yet a consistent gap exists between the two levels. This gap has been stably maintained for decades, indicating that it is structural rather than temporary.
“The number of believers exceeds the population, but faith levels are low” — this statistical contradiction arises from differences in what is being measured.
The Agency’s statistics are administrative data designed to grasp the operational reality of religious corporations, not to measure individual faith. Individual surveys, on the other hand, measure respondents’ subjective consciousness, but interpretations of “faith” and “religion” vary among people.
It is not a matter of which statistics are “correct,” but rather that each measures a different aspect. Religion as an institution and faith as personal consciousness do not necessarily overlap in Japan. This gap is not a flaw or error in statistics, but evidence of a structural condition in which institutional affiliation and individual faith have long been separated — a distinctive feature of religion in Japan.
