Animal Keeper - a JavaScript and HTML5 Canvas game
Last updated on January 2, 2015, 8:08 by Sebastian Mihai

I had wanted to code something in HTML5's Canvas for a while, and of course, I decided to make a little game.


You control a keeper who is trying his hardest to maintain the well-being of his animals. He can perform the following tasks:

move - click on any space on the playing field

pick up items such as food and medicine - click on the corresponding icon. The keeper will walk to it and pick it up. He can only hold one item.

feed animal/administer medicine - click inside of an animal enclosure. The keeper will automatically feed the animals in that enclosure, or administer the medicine, depending on what is being held at the time.

Note: when standing close to an animal enclosure, you can inspect the diet of the respective animal, in order to learn what to feed them.

Note: some foods are harmful to certain animals!

The game doesn't keep score. It's more like a simulation in that sense, but I think it is still fun to try to keep your animals happy. They will get sick and hungry quite fast. Be on your toes!

Click here to start


The game is based on the Canvas element in HTML5. I've made a few attempts to add sound as well, but had very poor results, and which varied wildly between browsers.

Since at every refresh (such as movement) the images have to be re-loaded (via setting the src attribute), I've converted the contents of my .png files to base64 and stored them as strings in Javascript. This means that the browser doesn't have to make a trip to the server to get them every time something moves on screen! The only image that is present is the playarea background, a large blended terrain texture.

You can download all game files locally (the directory can be accessed freely, listed, etc.), and tweak the code as you see fit. In particular, game balance constants are found at the beginning of globals.js.


The game works with Firefox 3, Firefox 4, and Internet Explorer 9 (click 'Allow blocked content').

The game does not work with Ice Weasel 3.

Compatibility with other browsers is unknown.

If you use the materials on this page, or any other page on this web site, you do so at your own risk. They are provided "as is". No warranty is provided or implied. I neither guarantee that the materials will work, nor that they will not be harmful in any way.

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