CodeDay (formerly StudentRND or SRND) is a non-profit organization which promotes STEM education for high school and college students.
 The organization is headquartered in Seattle, Washington and runs several programs for 55,000 students in 50 cities around the world focusing on "providing welcoming and diverse opportunities for under-served students to explore a future in tech and beyond."
 CodeDay was founded in 2009 by Edward Jiang as "Student Research and Development" (which is still the organization's legal name), and was initially a makerspace for students and high school accelerator, helping to start several successful companies. The early days of the organization were profiled in the book, Be a Changemaker: How to Start Something That Matters.
 The original mission of CodeDay was to "create the next generation of technologists" through makerspaces, however CodeDay closed its makerspace in 2013, citing lack of attendance and high costs, and began focusing entirely on CodeDay.
 Around the same time, CodeDay adopted a mission of increasing interest in Computer Science, as well as focusing on attracting diverse students. Despite this focus on diversity, it does not promote to any single demographic, reporting a combined diversity of 68% women, low-income, African American, and Latino students (compared to the industry norm of 14%).
 As of 2020, 36,594 students without experience had taken part in CodeDay's programs, and 25,681 continued to code.
 CodeDay started its core event program in 2012, a series of 24-hour programming competitions run across the US every few months, usually on long weekends.
 CodeDay is currently hosted in 48 cities, focusing on regions without robust tech sectors. All cities run CodeDays simultaneously, and are hosted at local tech companies or co-working spaces, and funded by local donations, sponsorships, and a $10 entrance fee, which some consider controversial.
 Events are 24-hours-long with pitches at the beginning and presentations at the end. Many students do not sleep and program for the entire event. During the events, there are workshops on various subjects, as well as a CTF called CodeCup. Many students who attend CodeDay have little or no experience before attending. The goal of CodeDay is to get these students to continue to pursue Computer Science after they leave.
 In response to COVID-19, CodeDay began hosting online CodeDay events in April 2020, called Virtual CodeDay. CodeDay started hosting its in-person events again in November 2021, but continued to host Virtual CodeDay.
 In early 2022, CodeDay expanded into Asia with the introduction of events in Singapore and Mumbai.
 In 2023, CodeDay hosted it's event on Lucknow, Amritsar and will host events on Kolkata, Durg, Bangalore and many other cities. 
 In 2013 CodeDay launched a summer program called StudentRND Labs which taught students skills of entrepreneurship. In 2017 the organization relaunched the Labs program as an entirely online program with focused on technology education and providing an experience similar to an internship, working on open-source software.
 The program runs from June through August and pairs college students up with full-time programmers from the technology industry to contribute to open source software. Though the program claims to try to replicate a traditional technology internship, some differences include that only 20 hours per week is required to participate, students are not hired by a particular company, and most students are not paid. There is also a "beginner track" which pairs high school students up with college interns.
 CodeDay also runs several other programs: