Top 20 Programming Languages of September 2025: See What’s Leading the Tech World!

Perl’s Unexpected Resurgence

In a ranking system like the TIOBE index, which usually shows little change from month to month, any notable shift attracts attention. Such is the case with Perl in recent weeks. Founded in the late 1980s by Larry Wall, this language reached its zenith in the mid-2000s, securing the third spot in 2005. For reasons still somewhat mysterious, it is experiencing a resurgence in popularity among developers. As of September 2025, Perl ranks as the tenth most searched language, a significant leap from twenty-seventh just a year earlier, a development that even surprises Paul Jansen, who analyzes the index’s monthly changes. “The only explanation I can think of is that Perl 5 is gradually being recognized as the real Perl”, he suggests.

According to TIOBE’s CEO, this momentum could be attributed to recent advancements in Perl 5, following the failed implementation of Perl 6, which lasted for years and was even renamed Raku. “Over these decades, the development of Perl 5 was more or less stagnant, leaving the Perl community in limbo”, he explains. Meanwhile, an attractive alternative, Python, developed, drawing many Perl programmers to it. Now, 25 years later, Perl 6/Raku ranks 129th in the TIOBE index, playing no significant role in the programming world. However, Perl 5 has been publishing more frequently lately, drawing more attention.”

The Top 20 Most Popular Programming Languages in September 2025

While Perl is regaining some developers’ interest, it remains well behind Python (25.98%), which continues to be the most popular language among developers, followed by C++ (8.80%) and C (8.65%). The top of the ranking remains stable, except for Delphi/Object Pascal, which has climbed two spots to now sit at ninth place.

Further down the list, other languages are showing good dynamics: Ada has climbed twelve places in September 2025, marking a 0.56% increase. R (+2), Scratch (+1), and Assembly language (+4) are also making gains, while Rust and MATLAB have fallen by four and seven places, respectively.

Here are the 20 most searched programming languages by developers in September 2025:

1. Python (= same position as in September 2024)
2. C++ (=)
3. C (+1)
4. Java (-1)
5. C# (=)
6. JavaScript (=)
7. Visual Basic (=)
8. Go (=)
9. Delphi/Object Pascal (+2)
10. Perl (+17)
11. SQL (-2)
12. Fortran (-2)
13. R (+2)
14. Ada (+12)
15. PHP (-2)
16. Scratch (+1)
17. Assembly language (+4)
18. Rust (-4)
19. MATLAB (-7)
20. Kotlin (-2)

Discover the complete ranking

What Are the Ranking Criteria of the TIOBE Index?

Launched in 2002 by TIOBE Software, this index assesses the popularity of programming languages among developers each month. To achieve this, the Dutch company relies on the volume of queries recorded across more than twenty search engines, including Bing, Google, Wikipedia, and Amazon. The primary goal of the TIOBE index is not to declare the “best” language but to identify those that are garnering interest, helping developers choose the most relevant language when starting a new project.