Early bird or night owl

Stack Overflow: Java peaks during the 9-5 workday while Angular does better in the evenings

Jane Elizabeth
© Shutterstock / Melnikov Daniil

Coding at night? It’s probably not in JavaScript. The data scientists over at Stack Overflow have done a deep dive and discovered when certain programming languages are used. Surprisingly, not a whole lot of people are asking questions on Stack at 5am. Who knew?

Are you an early bird or a night owl? Can we tell when specific programming languages are popular? It seems silly to ask, but knowledge is power. Also, timing your questions right on Stack Overflow could be the difference between getting a solution and googling error codes in desperation.

When it comes to data about developers and coding, Stack Overflow is a treasure trove of information. For example, some enterprising soul over there figured out you could in fact distinguish when people were coding and with what language, all by plotting the information of questions asked on the site. After all, people don’t tend to ask questions about Java ten hours after they run into a problem while they’re coding in Go, you know?


David Robinson, a data scientist at Stack Overflow, started off with a basic set of data by examining visits to Stack Overflow by the hour across four weeks in August 2016. Why August? Well, it avoids most Western holidays and school is still traditionally out of session in the Western hemisphere. (The data from all those CS majors staying up all night and practicing their C and Matlab might distort the results.)

For all of these visits, they approximated the time zone based on their IP address and calculated the local time.

First, let’s see when people visit Stack Overflow.

programming languages

“Stack Overflow helps programmers do their jobs, so it’s not surprising that our traffic spikes during the workday, with the site getting at least a million visits per hour between 9 a.m. and 5 p.m.,” says Robinson.

The trend lines on this one are pretty significant. During the week, visits to Stack Overflow on Monday through Thursday are fairly consistent. Friday is a bit of an outlier with a lower rate of visits, with a much lower hit rate in the afternoon. I guess everyone skips out early on Friday start their weekends ahead of time!

See more: DevOps and machine learning specialists are the best paid, says Stack Overflow

Weekends are considerably quieter for obvious reasons. Developers have a bit of a lie-in on Saturday and Sunday, possibly making up for some of those late nights.

Across the board, 5 am is quiet-sleepy-time on Stack Overflow, surprising absolutely no one. Also, the sharp dip at noon during the week correlates with lunchtime. I’m glad everyone seems to be grabbing a bite to eat.

Programming languages

So, timing is key if you want to get a question answered. 4:30 in the morning is probably not a great time to pose a tricky question. But how about the programming languages themselves? Are some languages more popular at different times?

In short, yes.

There’s a nifty interactive graph that lets you play around with different tags and see the results for the traffic per hour for specific languages. In this one, I looked specifically at Java, JavaScript, Angular 2, React.js, and Go. (Please note that this data is only Monday through Thursday, to avoid distortion due to Friday’s low rates of traffic and the slump Stack Overflow has on the weekends.)

programming languages

So, what can we see from this graph? A few things.

  • Java and JavaScript are work languages. They peak during the 9-5 workday and then crater at roughly 7 pm, when most people have left the office.
  • Angular and React also follow the general workday trends. They do slightly better in the evenings, suggesting they’re used by hobbyists or free-time coders as well.
  • Go is not as popular as the other programming languages during the day, but has a strong showing in the afternoon and evenings, supporting the assumption that it’s more of a free-time language.

Also, Stack Overflow has this nifty animation showing how the traffic flows actually work on the tags. It’s really cool.

programming languages


So, we can see that, on average, people tend to visit during the work week between the hours of 9am and 5pm. But is that the same all over the world? Stack Overflow is used by a fairly international crowd; developers in San Francisco and Seoul can have pretty different lives.

See more: Technology trends 2017: Here are the top programming languages

Here, Robinson looked at the 50 cities with the highest amount of Stack Overflow traffic during the month of August 2016. Which cities were developers more likely to visit between 9 to 5, or on their off hours?

programming languages

Clearly, the cities that kept to a strict 9-to-5 schedule were in Western Europe, including London, Paris, and Amsterdam.  Cities with more nontraditional hours were either in Asia, like Tokyo or Seoul; Eastern Europe, like Moscow or Kiev; or along the west coast in the United States, like San Francisco and Los Angeles.

Why the disparity? Perhaps developers are staying up late because they are working so hard. More likely, they are working on a staggered schedule to collaborate with colleagues in Western Europe or on the east coast in the United States.


There’s a lot to be learned by digging through the data. We can find that some programming languages are clearly for work or for hobby use, just by the number of questions posed on Stack and when they are posted. We can also track work schedules and traffic rates around the world. It’s pretty fascinating stuff, really. So, if you’re interested, head on over to Stack Overflow and see the data for yourself.

As for me, next time I have a sticky coding problem, 11am on a Thursday sounds like the best possible time to post. You’re probably going to have better luck than 6am on a Sunday, for sure.

Jane Elizabeth
Jane Elizabeth is an assistant editor for

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