Senior Software Engineers at Google write an average of 20 lines of code per day, which equates to 5000 lines per year. As for Junior Software Engineers, on average they write 100 lines of code per day totalling 25,000 lines per year.

Google employs 27,169 software engineers, as of January 2024. It’s difficult to gauge the number of Senior vs Junior Engineers at Google from online sources. However, with some simple maths, if all were Senior, it would mean Google sees 135,845,000 lines of code annually.

If there were 3 Juniors to every Senior, it would mean Google has 543,380,000 new lines of code per year.