Andrzej Mazur
HTML5 Game Developer, JavaScript Programmer and Mozilla Tech Speaker. Enclave Games indie studio founder, Gamedev.js Weekly newsletter publisher and js13kGames competition creator. Likes eating sushi and playing Neuroshima Hex.
Js13kGames is a JavaScript coding competition for HTML5 Game Developers. The fun part of the compo is the file size limit set to 13 kilobytes. The competition will start at 13:00 CEST, 13th August and end at 13:00 CEST, 13th September 2019. Theme for 2019 will be announced on 13th August.
Read GitHub's tips and tricks article, check the Resources for tools,
read the Blog, and subscribe to the Newsletter - good luck and have fun!
The competition is organized by Andrzej Mazur from Enclave Games.
I'm running this competition on my own
in my free time. I usually acquire prizes worth more than 20.000 USD and send special js13kGames t-shirts to top participants for free. With gadgets and stickers, every single year, with free shipping.
To help me keep it all going you can send a few bucks via the PayPal button below, thank you!
Want to help? Your company can become a partner, offer a prize, promote the competition, or help in any other way?
Please get in touch, thank you!


Share the love for HTML5 games and support the js13kGames competition!
See the Contact section for more details on how to get in touch.
HTML5 Game Developer, JavaScript Programmer and Mozilla Tech Speaker. Enclave Games indie studio founder, Gamedev.js Weekly newsletter publisher and js13kGames competition creator. Likes eating sushi and playing Neuroshima Hex.
Creator and lead developer of TwilioQuest, a PC game (built with web technologies) designed to challenge a generation of software developers to change the world with code. After writing JavaScript for the last decade and founding JavaScriptMN, one of the Twin Cities' most active technical user groups, you'd assume he's better at JavaScript than he actually is. Kevin lives just outside Minneapolis with his wife and three devious children.
Creator of 50 games, 80 songs, 2 books, and One Game A Month. Mentor-in-residence at the Gamkedo game development club.
Maciej Szpyra, Michał Nykiel, Paweł Skierczyński and Victor Debone. Developers during the day, gamers during the night. At Spartez, our personal passion for games was big enough that we needed to bring more team members to the jury, and we are ready to play all the games coming from 2019 developers 🕹🕹🕹 with some expectations from multiplayer games.
Co-founder and owner of Jscrambler where he co-leads business development, and supervises all R&D and technical activities. Inventor and co-author of several JavaScript-related patents in Application Security. Holds a degree and a MSc in Computer Science. Speaker at several IT events, related with Security and JavaScript.
Christof Wegmann is founder and CTO of Exit Games and develops the realtime, multiplayer, cross-platform product "Photon". Photon is used by more than 300,000 game developers - including companies like Square Enix, Ubisoft, Disney, Warner Bro, SEGA, Miniclip, Codemasters, Glu, Rilisoft or World Golf Tour. The high performance Photon Server and Photon Cloud allow cross-platform gaming between Mobile, PC, Console, Web, VR/AR and other popular devices.
Creator and developer of GDevelop, a game creation tool accessible to everybody and built on JavaScript. Made Lil BUB's Hello Earth game, an 8-bit game starring the internet sensation cat. Big fan of JavaScript to create everything, from apps to games!
Expert's short description.
Expert's short description.
Expert's short description.
Five courses combined into Super Combo Pack 1 – Build Arcade Games with Phaser 3 from Jared York.
Three lifetime and ten year-long licenses for Phaser Editor from Arián Fornaris.
Thirteen paid GitHub Pro plans - personal accounts with unlimited private repositories for twelve months each.
One hundred copies of Evil Glitch game by Agar3s available on Steam.
Five coupons for the online HTML5 Game Development Mini-Degree from Zenva Academy.
Five coupons for the online Full-Stack Web Development Mini-Degree from Zenva Academy.
Three Personal licenses for one year each of Construct 3 game engine created by Scirra.
Ten 6-month PlayCanvas Personal accounts offering a cloud-hosted, collaborative platform for building games.
Ten copies of Danger Crew game by Team Danger Crew available on Steam.
Three Jscrambler Startup licenses for three months each.
Fifteen copies of Pyxel Edit pixel art editor by Daniel Kvarfordt.
Three CodePen Pro Starter accounts with lots of cool features for 12 months.
Prize's description.
Prize's description.
Prize's description.
There are four different categories, you can submit your game to any of them - it's up to you.
There's a special page for everything about the new WebXR category if you want to know more.
Full power of the hardware.
Handheld touch devices.
Node.js multiplayer.
Virtual reality.
We will also have the famous Community Awards voted among all the participants.
All your code and game assets should be smaller than or equal to 13 kilobytes (that's exactly 13,312 bytes, because of 13 x 1024) when zipped. Your .zip package should contain index.html file and when unzipped should work in the browser. Don't overcomplicate building the zip package, it should unpack on any platform without problems. You can use tools that minify JavaScript source code.
The competition is focusing on the package size, but learning from others is also very important. Please provide two sources of your game - first one should be minified and zipped to fit in the 13 kB limit (sent via the form) and the second one should be in a readable form with descriptive variable names and comments (hosted on GitHub).
You can't use any libraries, images or data files hosted on server or services that provide any type of data - for example Google Fonts are not permitted (although you are allowed to ask users to live-load a web font to support some characters or emoji on devices that can't display them properly, but you have to make sure your game will work without them). Your game should work offline (Desktop and Mobile categories) and all the game assets should fit in the package size limit (not counting WebXR's A-Frame and Babylon.js frameworks). If you manage to shrink your favorite library below 13 kilobytes including the code itself, then you can use whatever you want, just remember about the 13 kB limit.
Main theme for the competition will be announced on 13th August. It's highly advised to follow it in your game, because the judges will pay attention to that, but you can freely interpret the theme and implement it however you feel would be the best.
The competition starts at 13:00 CEST, 13th August 2019 and ends at 13:00 CEST, 13th September 2019. No submissions will be accepted after the end of the competition.
You have to have the rights for every asset used in your game. Remember that the submitted games will be published and made available for everybody to see.
Do not submit any old games or demos - you have a whole month to work on something new and fresh, this should be more than enough. Also, submitting Breakout or Flappy Bird clones taken out of a tutorial make no sense at all - try creating something at least a little bit more original.
Your game must work and be playable in at least two browsers: latest Firefox and Chrome, but the more supported browsers, the better. There should be no errors - you can lose some points if your game is showing any errors in the console. If we cannot play your game, it won't be accepted.
It doesn't matter if you're working alone or with your friends, just remember that the number of prizes is fixed, so you'll have to share your trophies with your teammates.
There's a special form to submit your game. Please remember that you have to provide two sources (see the Rule #2 for details) - a link to a public repository on Github and a zipped package. Participants are allowed to submit more than one game in the competition, though sending the same game as independent submissions targeting different platforms (for example separate builds for desktop and mobile) is forbidden.
Submissions will be checked manually and published after positive verification. This may take up to a couple of days, so be patient if your game is not yet online. I claim the right to reject any submission without giving a reason, although I hope I don't have to. I also have the right to update the rules of the competition at any time.
The voting among the participants will last for three weeks between September 13th and October 4th, winners will be announced on October 5th. Experts will give the games constructive feedback (one per game) during the same three week period - their comments will be published on October 4th.
All the Server category rules, the sandbox server and the demo code can be found at github.com/js13kGames/js13kserver.
All participants and judges at js13kGames are required to agree with the following code of conduct. Organizers will enforce this code throughout the online event. We are expecting cooperation from all participants to help ensuring a safe environment for everybody.
Js13kGames is dedicated to providing a harassment-free competition experience for everyone, regardless of gender, sexual orientation, disability, physical appearance, body size, race, or religion. We do not tolerate harassment of competition participants in any form. Competition participants violating these rules may be sanctioned or expelled from the competition at the discretion of the competition organizers. TL;DR: Be excellent to each other.
By entering your email address and sending a game through the submit form you agree to receive email communication about important events of the competition like announcing the winners or sending out the digital prizes, but also curated content from the partners about their tools, services, or job offers. I will never share your email with anyone though.
If You have any questions or propositions please feel free to contact us via e-mail: contact@js13kgames.com.
The other options include visiting our profiles on Twitter or Facebook,
or joining our Slack channel and sending us the private message.