Fortran, Delphi rise in Tiobe popularity index

Older programming languages such as Fortran and Delphi are making a comeback, based on the results of this month’s Tiobe index of language popularity. Tiobe attributes their rise to the need to maintain vital legacy systems still dependent on them.

Fortran and Delphi are competing for a top 10 spot in the index, with Delphi/Object Pascal ranking 10th and Fortran 11th in the Tiobe index for March 2025, published March 10. Ada, ranked 18th, and Cobol, ranked 20th, also are trending upward. Fortran ranked 10th as recently as January.

Tiobe CEO Paul Jansen found it interesting to see these four “very old languages” sneaking into the top 20. “I think that it has to do with the many vital legacy systems that keep the world running,” he said. “Most of them are developed with the aid of these dinosaur languages. Now that the last of the core developers of these systems are about to retire, companies avoid any risk and choose to keep the existing systems and even extend them rather than replacing them by newer systems based on more modern languages.” These languages have evolved and are pretty up-to-date, he added.

The ratings in Tiobe’s index are based on the number of skilled engineers worldwide, courses, and third-party vendors pertinent to a language. These are calculated using Google, Bing, Amazon, Wikipedia, and more than 20 other websites.

The Tiobe index top 10 for March 2025:

1. Python, with a rating of 23.85%
2. C++, 11.08%
3. Java, 10.36%
4. C, 9.53%
5. C#, 4.87%
6. JavaScript, 3.46%
7. Go, 2.78%
8. SQL, 2.57%
9. Visual Basic, 2.52%
10. Delphi/Object Pascal, 2.15%

The rival Pypl Popularity of Programming Language index ranks the languages by analyzing how often they are searched on in Google.

The Pypl index top 10 for March 2025:

1. Python, with a share of 30.27%
2. Java, 14.89%
3. JavaScript, 7.78%
4. C/C++, 7.12%
5. C#, 6.11%
6. R, 4.54
7. PHP, 3.74%
8. Rust, 3.14%
9. TypeScript, 2.78%
10. Objective-C, 2.74%