How to publish a browser game: answers for developers
You drop the game as a ZIP, a whole folder or a single HTML file, an automatic check runs in minutes, and a person from klyo looks at the game and lets it into the catalogue. The fastest way from upload to catalogue took 3 min, typically it takes about 2 h. Below are the questions developers ask most, with numbers from the live portal.
Numbers from the klyo games catalogue, as of the day this page was built.
Where should I publish a browser game?
On klyo games a game gets, for free, its own address, a catalogue page in four languages, online rooms without your own server, leaderboards, saves and clips, and an AI assistant can publish and fix it through MCP.
Online works in every game through the same klyo kit: rooms with a code and a link, quick match, bots in empty seats, up to 64 players in turn-based games and 16 in real-time ones, with no server on your side. An AI assistant (Claude, ChatGPT) has 22 MCP tools: it uploads the package, reads diagnostics, publishes new versions, translates the description and shows player data. We do not ask for exclusivity. A comparison with CrazyGames and itch.io, sourced from their documentation, is on the “For developers” page.
When will my game appear in the catalogue?
Usually the same day: the fastest way from upload to catalogue took 3 min, typically it takes about 2 h.
After the upload an automatic check runs on the package and the game works at its own address g-your-game.klyo.pl right away, so you can play it and send the link to testers. Then a person from klyo looks at the game. Only after that is it in the catalogue, in the portal search, in the leaderboards and in Google, and its description is translated into more languages. The game's catalogue page is built about a minute and a half after approval.
What do you check before a game reaches players?
Two things: an automatic check of the package and how the game runs, and a person who looks at the game itself.
The automatic check rejects a package with missing files, errors that stop the game, malicious code or ads from other networks. It also checks that the game reports it is ready through the klyo kit, that a phone game reacts to touch and that a game which promises a leaderboard really sends a score. It warns (without blocking) about other companies' brands in the files and unclear asset licences. For every reason the studio shows the file, the place and how to fix it.
My game was rejected. What now?
The developer studio shows the reason and how to fix it, and after the fix you send the same game again, without creating a new one.
A rejection is not an account ban or a penalty: it tells you what a player would not get past, such as a white screen on a phone or an empty leaderboard. Usually you fix one file and upload a new package to the same game. If you work with an AI assistant, the MCP diagnostics tool gives it the same reasons, so it can fix the game itself.
How do I publish a new version without players losing progress?
Upload a new package to the existing game: the address, leaderboards, reviews and player saves stay, only the game files change.
A save belongs to the game and the player's device, not to a version, so after an update players continue where they stopped. A new version passes the same automatic check as the first one, and the old one runs until you replace it. Do not create a second game for a new version: you would split players, leaderboards and the Google ranking across two pages.
How do I export a game from Unity, Godot, GameMaker or Construct?
Export the game for the browser (HTML5 or WebGL) and drop the whole export folder, a ZIP or a single HTML file into the studio. The browser builds the package: it takes the game out of its parent folder and leaves out files a browser cannot run.
Unity: WebGL build, ideally with Brotli compression or none. Godot: Web export. GameMaker: HTML5 export (GX.games is not needed). Construct and GDevelop: HTML5 export. Phaser, PICO-8, Defold and hand-written code work the same way. If an engine builds file names while the game runs, upload the ZIP from the export, not an address from another site: the check will then show what is missing.
How big can a game be?
The ZIP package can be up to 350 MB, and up to 700 MB unpacked.
The smaller the game, the faster it starts on a phone, and that decides whether a player stays. Compress large textures and sounds (WebP or KTX2 for images, Ogg or AAC for audio). One player's cloud save can be up to 64 KB.
Can I make a multiplayer game?
Yes: online rooms work through the klyo kit without your own server, up to 64 players in turn-based games and up to 16 in real-time games.
Players join from an invite link or through quick match, and empty seats can be filled by the game's bots. Moves travel over one klyo connection, in order and with retries after a dropped connection. A game that needs its own match server can register it in the developer studio. Sample code and a comparison with networking services are on the page “An online multiplayer browser game without your own server”.
How do I add a leaderboard and saves?
With one line from the klyo kit: send the score with klyo.score and the save with klyo.save, with no server and no player accounts.
Daily, weekly and all-time records, the player's position and how far they are from the next person show up by themselves under the game and at the end of a round. Scores are checked on the server, so a typed-in record does not reach the board.
Will my game be in Google, and in which languages?
Yes: after approval the game gets its own catalogue page in Polish, English, Ukrainian and German, and the game's text can have up to 10 languages.
You can write the description yourself in several languages or accept a translation prepared for you: in the studio you see every text before approving it. The page enters the sitemap for Google once it has enough content to be more than a tile. The studio shows what is missing for indexing in each language.
How will players find my game?
Through the catalogue and the portal search, the game's pages in Google, gameplay clips and the next-game suggestion after every round.
After a round in any game the portal suggests the next one based on what the player played longest, so a new game also gets players from other games. Short clips from your game appear in the clips bar and lead straight into the game. Leaderboards and player ranks give a reason to come back tomorrow.
How much does publishing cost, and who owns the game?
Publishing is free, and the rights to the game stay with you.
We do not ask for exclusivity: you can have the same game on itch.io, CrazyGames or your own site. You only allow us to show the game to players on the portal. The details are in the developer terms.
What age rating will my game get?
It comes from a content questionnaire like the one in app stores: 10 questions about violence, fear, language and similar content.
From it the game gets an age label and a decision about ads. An adult game is visible in the catalogue, but the player confirms their age before the first round.
Can an AI assistant publish and fix the game for me?
Yes: Claude, ChatGPT and other assistants connect to klyo through MCP and have 22 tools, from uploading the package to diagnostics and new versions.
The assistant uploads the package, prepares the description, reads the reasons from the check and fixes the game. A game published by an assistant waits for your click in the studio: you decide when it reaches players. When an assistant tries to publish a changed game as a new one, klyo tells it to upload it as a new version of the existing game.
When will I start earning from my game?
When Google ads go live on the portal: then you get 70% of the net ad revenue attributed to your game. Ads are not running yet and no ad revenue has been paid out.
A month's revenue is split between games by the number of plays, and the payout goes by bank transfer from 100 PLN. The plays you collect now are not lost: they build the game's position in the catalogue and in Google.
What player data will I see?
In the studio you see where players drop off: opening the page, pressing “Play”, loading, the first move, 30 seconds of play, a score, the end of a round and moving on to the next game.
Plus the levels where players fail or finish, your own game events, a map of places on screen and the load time separately on phones and computers. These are numbers without players' personal data. Your AI assistant gets the same data through MCP together with a ready list of things to fix.
Publish your game
Create a developer account, upload your package and play your game at its own address today.