Case Study: Code.org scales to support 25+ million Hour of Code users with BlazeMeter load testing

How Code.org Load Tested its Site for Over 25 Million Users

Code.org is a U.S.-based non-profit that promotes computer science education worldwide. Faced with The Hour of Code — a week-long global event expected to attract tens of millions of students — the small team had only two weeks to ensure the site could handle unprecedented traffic spikes across multiple countries.

They used BlazeMeter to run rapid, large-scale, multi-region load tests, iteratively finding and fixing bottlenecks, then scaling AWS servers and database capacity and preparing a read-only fallback. The result: stable performance during the events, supporting about 15 million users in 2013 and over 25 million in 2014, and making pre-event load testing a regular part of their preparation.

Code.org

Brendan Reville

Software Engineer