Browsercraft: Java Minecraft in the browser

by John7878781on 3/31/2025, 2:56 PMwith 101 comments

by waveringanaon 3/31/2025, 4:39 PM

When I was in fourth grade, I'd take the half a mile walk to the library almost daily which always made my parents happy because they assumed I was going to read, but instead I was hopping onto their computers, going to http://minecraft.net, and playing minecraft on IE :)

Thanks for the nostalgia

by nullbyteon 3/31/2025, 4:41 PM

Funny enough, the original version of minecraft used to run in the browser too! It used Java applets. That was a long time ago, I remember playing it as a kid

by gavinrayon 3/31/2025, 4:18 PM

5 years ago, I watched a YouTube recording of a meetup talk given by one of the CheerpX engineers:

https://www.youtube.com/watch?v=7JUs4c99-mo

In it, they showed a functional demo of porting an OSS multiplayer C++ game entirely to the browser with WASM.

Afterwards, I read some of their engineering content and was blown away.

It's been fascinating to watch the CheerpX/CheerpJ progress from afar over the years.

by apignottion 3/31/2025, 5:34 PM

Hi everybody, happy to see our CheerpJ demo is appreciated.

CheerpJ is a WebAssembly-based JVM that can run unmodified Java 8 and Java 11 applications. Java 17 will be supported later in year.

I am the lead developer of CheerpJ and CTO of Leaning Technologies. AMA.

by SunkBellySamuelon 3/31/2025, 3:18 PM

This is the main way I used to play Minecraft in the Beta days, thanks!

by AlphaWeaveron 3/31/2025, 9:39 PM

Another comment mentions MinecraftForFree.com...

In middle school, in an attempt to get around the school firewall, I copied the HTML code from that website to my own to play Minecraft at school. Since my domain wasn't on the blocklist, it worked! But when my friends started using it to play, even after they hadn't bought the game, I resolved to add a login wall.

I built a backend proxy in PHP that would POST their credentials to the Minecraft API to make sure they had purchased the game. I still think it's funny to think I had no ethical qualms about circumventing the school firewall, but piracy was where I drew the line.

by whalesaladon 3/31/2025, 3:18 PM

We have come full circle #applets

Twenty years ago running java in the browser would have just been called "using the internet"

by ConfusedDogon 3/31/2025, 7:13 PM

I used to love Minecraft as a kid until my kid ruined it for me. This 5-year-old loves to be in Creative mode and put me in Survival mode and set up traps and rounds of enemies for me to fight my way out. Not relaxing at all anymore.

by OsrsNeedsf2Pon 3/31/2025, 5:29 PM

The fact I'm playing this at 20 FPS on Firefox with a RX 7600 shows how much web browsers have regressed in 10 years, not how much they've advanced.

by pfoofon 3/31/2025, 4:48 PM

The craziest part is that it executes on my iPhone SE 2020 in Safari. Textures work, shading works, pretty insane. I even managed to break a block.

by Jotaleaon 3/31/2025, 5:21 PM

There's also Eaglercraft, which achieves the same result, but it has functioning multiplayer, and runs up to version 1.8.9, though you'll need a beefy computer.

by neuroelectronon 3/31/2025, 4:55 PM

There already is Minecraft in the browser implementations that are quite performant

https://map.realismc.com/#world:-87986:65:-25312:0:-0.01:1.5...

This is a world featuring llm powered players that make their own plans and constructions (using the terminal)

by CobrastanJorjion 3/31/2025, 5:14 PM

Great. We brought back Applets.

by __jonason 3/31/2025, 3:29 PM

Huh, is Minecraft Java edition free now? I haven't played in a long time but I thought when you download the regular client you only get to play after signing in with an account that purchased the game, how is this thing just starting the game directly?

by burgeroneon 4/1/2025, 5:30 AM

There's a similar but "illegal" other client called eaglercraft. It bumps this up a notch with a much more "recent" version of MC, by compiling java to javascript

by pidgeon_loveron 4/1/2025, 12:26 PM

Is this at all related to Eaglercraft (web: https://eaglercraft.com/, src: https://git.eaglercraft.rip/eaglercraft), which is also browser-based Minecraft?

by apion 3/31/2025, 5:14 PM

It's too bad that this kind of thing is using x86 as the actually-pseudocode for this. I understand why -- ease of porting, etc. -- but using either WASM (w/WALI?) directly with a kernel compiled to WASM (there are efforts to do this) or something open like RISC-V would be better long term.

by kevmo314on 3/31/2025, 3:31 PM

It crashed for me :(

    [failed to get system properties (java.lang.RuntimeException: No OpenGL context found in the current thread.)]
Applets were a real vibe. The gradient-blue UI that came out of the box is true nostalgia.

by bobdigiton 3/31/2025, 10:22 PM

We've gone full circle! Java was originally created to run apps in the browser.

by earth2marson 3/31/2025, 3:58 PM

how to do fullscreen?

by greatgibon 3/31/2025, 10:29 PM

And in the meantime, this shitty Roblox still doesn't run on Linux...

by butzon 3/31/2025, 3:34 PM

Playing Minecraft without Microsoft account? That doesn't look safe.