According to one of the analyses made by Pew Research, it was found that about one third out of the 196 countries in the world have religious symbols in their National Flags. Out of the 64 countries in this category nearly half of the flags have Christian symbols in them while about a third have Islamic religious symbols in them. This indicates the percentage of flags consisting of religious symbols with the two largest religious groups in the world.
Christian symbols were found in 31 flags including the countries from Asia, Europe, the Pacific and the Americas. Islamic symbols were found in the flags of 21 countries from sub-Saharan Africa, the Asia-Pacific region, North Africa and the Middle East.
Israel is the only country to have Jewish symbol in its national flag including the Star of David along with a white and blue striped background representing the Jewish prayer shawl.