Perl, a once-popular programming language that dates back to 1987, has seen a resurgence in the Tiobe index of language popularity. The language ranked 10th in this month’s Tiobe index, having risen from 27th one year ago. Perl ranked as high as third in its heyday.

In a bulletin accompanying the September 2025 edition of the index, published September 8, Tiobe CEO Paul Jansen said that the “technical” reason for Perl’s high ranking today is the huge number of books about Perl on Amazon. “It has four times more books listed than for instance PHP, or seven times more books than Rust,” Jansen said. He speculated that the underlying “real” reason for Perl’s resurgence may be that Perl 5, which was rolled out in 1994, is now gradually being considered the real Perl. The implementation of Perl 6, which arrived December 25, 2015, took decades to develop and was eventually rebranded as Raku, he added. “During these decades, the old development of Perl 5 stalled more or less, and as a result the Perl community was left with uncertainty,” Jansen said. “At the same time, a nice alternative, Python, matured, and many Perl programmers moved to Python.”

Ratings for the monthly Tiobe Programming Community index are based on the number of engineers worldwide, courses, and third-party vendors pertaining to each language. These are determined using websites such as Google, Bing, Wikipedia, and Amazon.

The Tiobe index top 10 languages for September 2025:

1. Python, 25.98%
2. C++, 8.8%
3. C, 8.65%
4. Java, 8.35%
5. C#, 6.38%
6. JavaScript, 3.22%
7. Visual Basic (2.84%
8. Go (2.32%
9. Delphi/Object Pascal, 2.26%
10. Perl, 2.03%

The alternative Pypl Popularity of Programming Language Index is based on how often language tutorials are searched on in Google. The Pypl index top 10 for September 2025:

1. Python, 29.69%
2. Java, 14.72%
3. C/C++, 9.27%
4. JavaScript, 6.79%
5. R, 5.26%
6. C#, 4.81%
7. Objective-C, 4.17%
8. PHP, 3.34%
9. Rust, 2.73%
10. Swift, 2.72%