Five Nights at Osaka's now has an HTML version.

In comparison to the .exe file, the HTML version appears to generally be much more unstable and laggy when first running the game. The HTML version's performance is also highly impacted by how powerful one's device is, so most likely on mobile devices or lower-end computers the game will run very poorly.

We recommend using the .exe version, but if you absolutely have to, the HTML version might suffice.

Unsupported browsers: Opera, Opera GX