
Modern Model Format
Allows 1.21.11 models to load in older versions
Screenshots

About this Mod
Allows the use of the 1.21.11 model format in older versions with the help of black magic, specifically allowing all three axis (XYZ) rotation and incrementes larger/smaller than 22.5°, additionally removing the 3x3x3 size constraint.
Example

Model
File: assets/minecraft/models/block/diamond_block.json
{
"format_version": "1.21.11",
"textures": {
"all": "block/diamond_block"
},
"elements": [
{
"from": [0, 0, 0],
"to": [16, 16, 16],
"rotation": {"x": 45, "y": 45, "z": 45, "origin": [8, 8, 8]},
"faces": {
"north": {"uv": [0, 0, 16, 16], "texture": "#all"},
"east": {"uv": [0, 0, 16, 16], "texture": "#all"},
"south": {"uv": [0, 0, 16, 16], "texture": "#all"},
"west": {"uv": [0, 0, 16, 16], "texture": "#all"},
"up": {"uv": [0, 0, 16, 16], "texture": "#all"},
"down": {"uv": [0, 0, 16, 16], "texture": "#all"}
}
}
]
}
Supports both rotation types:
All axis rotation
"rotation": {
"x": 45,
"y": 45,
"z": 45,
"origin": [
8,
8,
8
]
}
Single axis rotation
"rotation": {
"angle": 45,
"axis": "y",
"origin": [
8,
8,
8
]
}
Issues
If you have found an issue please report it on the github, along with (if applicable):
- any logs
- the model
- a screenshot
- the game version
- modlist
My models are not loading anymore
Try checking the model file for any extra brackets {} because Modern Model Format ensure a strict json validation.
Example:
[18:30:32] [Worker-Main-2/ERROR]: Failed to load model mod_id:models/item/example_item.json
com.google.gson.JsonSyntaxException: com.google.gson.stream.MalformedJsonException: Use JsonReader.setLenient(true) to accept malformed JSON at line 1 column 506 path $
Available Versions
How to Install Modern Model Format on Your Server
Order Server
Order a Minecraft Java server with at least 3 GB RAM (4 GB recommended).
Set fabric Loader
In the panel under "Egg", select the fabric loader and matching Minecraft version (1.21.3).
Install Mod
Open the mod browser in the dashboard and search for "Modern Model Format". Click "Install" – done! Alternatively, upload the .jar via SFTP to the /mods folder.
Compatibility
Mod Loaders
Minecraft Versions
1.21.3, 1.21.2, 1.21.1 (+10 more)
Server-side
✗ UnsupportedRecommended RAM
4 GB(min. 3 GB)Frequently Asked Questions
Modern Model Format server crashes on startup – what to do?
Most common cause: wrong fabric version or insufficient RAM. Check the server log (latest.log) for "OutOfMemoryError" or "Mixin" errors. With Mado Hosting: ensure at least 3 GB RAM is allocated and the loader matches the mod version (1.21.3). You can switch loaders with one click in the panel.
Is Modern Model Format compatible with fabric?
Modern Model Format officially supports fabric for Minecraft 1.21.3, 1.21.2, 1.21.1. The Mado dashboard automatically detects incompatible loader combinations.
Server lagging with Modern Model Format – how to optimize performance?
Recommended RAM: 4 GB (per 8 players). Use /spark profiler to check if Modern Model Format consumes the most tick time. Common fixes: reduce server view-distance to 8-10, install "performant" or "starlight" as supplementary mods on Forge. With Mado Hosting, your server runs on NVMe SSDs with dedicated CPU cores for minimal latency.
Rent Modded Server
Install Modern Model Format with just one click on your server.

