The js13kGames competition is returning this August for its 14th edition – and yes, it’s all about building a JavaScript game under 13 kilobytes in size. The challenge will begin on August 13th, 2025, so if you’re into tiny, clever, and creative web games, now’s the perfect time to start thinking about your entry.
Every year, developers from around the world come together to compete in this uniquely restrictive format. With a hard limit of 13 KB (zipped), participants must pack gameplay, graphics, sounds, and logic into a single, minified bundle. It’s both a technical and creative challenge — and a fan favorite in the web gamedev community.
What’s new this year?
While the full details and theme will be announced on day one of the competition, expect a mix of returning categories (like WebXR and Decentralized) and some possible surprises. There are also new partners and sponsors expected to join the lineup, which usually means more prizes, tools, and community perks.
If you’re curious about how the competition evolved over time, check out our wrap-up of js13kGames 2024 where we covered the winners, highlights, and trends from last year’s entries.
Why join js13kGames?
There are multiple benefits of joining the competition.
- Creative limitations: build something meaningful within 13 KB zipped — learn compression, code golfing, and clever tricks.
- Community: connect with a global network of developers, artists, and tinkerers.
- Prizes: winners in each category typically receive physical and digital prizes from well-known industry sponsors.
- Portfolio boost: many past participants landed jobs, collaborations, or attention thanks to their tiny games.
Tips for getting started
Even though the compo officially begins in August, there’s plenty you can do now to prepare:
- Revisit past winners on js13kgames.com for inspiration.
- Set up a local boilerplate or use the starter template.
- Explore compression tools like Roadroller.
- Think about simple mechanics that can be expressed in minimal code.
The competition supports pure JavaScript with no external libraries, so you’ll need to rely on your own ingenuity and small-scale optimizations, or use micro libraries like Kontra or LittleJS.
Mark your calendars: August 13, 2025
Get ready for a month-long journey into code efficiency and creative game design. The official countdown has begun. Whether it’s your first time or you’re a returning veteran, js13kGames is one of the most fun, challenging, and rewarding experiences in JavaScript game development.
Casey Vega is a contributor to Gamedev.js, assisting with writing, editing, and curating content around game development and the web tech ecosystem.
