Forge Config API Port Needed by Better Compatibility Checker 21.3.1
requiredMatching file found Matched file: v21.4.3-1.21.4-Fabric
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Modrinth · Minecraft mod
Better Compatibility Checker
Changes the default server compatibility check to compare modpack versions
Choose a version Pick your version below, then grab the matching file.
Quick answer
Which Better Compatibility Checker release matches 1.21.4 Fabric?
Best match for your filters 21.3.1
Game version 1.21.3, 1.21.4, 1.21.5
Loader Fabric
Better Compatibility Checker 21.3.1 targets 1.21.3, 1.21.4, 1.21.5 with Fabric. Installation on the client is optional. Installation on the dedicated server is optional. 1 required mod needs a matching file.
Where it goes
Is Better Compatibility Checker required on the client, server, or both?
Installation on the client is optional. Installation on the dedicated server is optional.
Client Optional
Dedicated server Optional
Loader for this release Fabric
Required install it here Optional supported, not mandatory Not supported do not install here Source doesn’t say do not assume
The source marks this as usable on both the client and server.
What else does Better Compatibility Checker 21.3.1 need?
21.3.1 on 1.21.4 Fabric. Every mod below is checked against that same setup.
Install Forge Config API Port, Fabric API first, but 1 required mod has no matching file for this setup. Do not mix loader builds to force a match. 1 comes through another mod in the chain.
2 listed on this file 1 pulled in by one of those mods
Fabric API Needed by Better Compatibility Checker 21.3.1
requiredNo matching file
Forge Config Screens Needed by Forge Config API Port
pulled inNo matching file
1 extra mod was pulled in by another dependency. Indented rows show who needs each one. We only count dependency files that match this setup. A file for another loader does not fill the gap.
Before you install it
Add Better Compatibility Checker without breaking your instance.
Built for Better Compatibility Checker 21.3.1 on 1.21.4 Fabric. Pick another file and the loader, install side or required mods may change.
- 01
Stick to this file
Use 21.3.1. It targets 1.21.3, 1.21.4, 1.21.5 with Fabric; another release may have different loader, side or dependency requirements.
- 02
Bring the mods it needs
Install Forge Config API Port, Fabric API first, but 1 required mod has no matching file for this setup. Do not mix loader builds to force a match. 1 comes through another mod in the chain.
- 03
Put it on the correct side
Installation on the client is optional. Installation on the dedicated server is optional.
- 04
Pick the file you checked
Use the “Get this file” button beside 21.3.1. It opens that exact file at the source.
About this project
What does Better Compatibility Checker add?
The forge server compatibility checker is not always accurate and can cause some issues with end-users of a modpack when they add a server, and it shows up as not compatible.
This mod fixes that issue when used by modpacks, as it will compare the modpack project ID and the modpack version ID set in a config file by the modpack author and display a tick if they match or an X if they do not match.
Both server and client are running the same version
Incompatible server or client version
How do I configure the mod?
It's simple to configure the mod, first, you will need to open the bcc-common.toml in the config folder, then you will need to set the modpack name and the modpack version, click save, and you're done.
Just remember to update the version when you update the modpack.
Note: Fabric config is named bcc.json
What happens if the mod is not installed on the server, but is on the client?
This mod will check if the data needed is set first and if it's not it will fall back to using the default forge implementation
All Rights Reserved unless stated otherwise. Distribution permission is given to FeedTheBeast for use in modpacks
Project description from Modrinth.
Pick your setup
Better Compatibility Checker by Minecraft version and loader
Choose the version and loader you play, then open the matching release.
Minecraft version
26.2
2 loader buildsMinecraft version
26.1.2
2 loader buildsMinecraft version
26.1.1
2 loader buildsMinecraft version
26.1
2 loader buildsMinecraft version
1.21.11
2 loader buildsMinecraft version
1.21.10
2 loader buildsMinecraft version
1.21.9
2 loader buildsMinecraft version
1.21.8
2 loader buildsMinecraft version
1.21.7
2 loader buildsMinecraft version
1.21.6
2 loader buildsMinecraft version
1.21.5
2 loader buildsMinecraft version
1.21.4
2 loader buildsShowing the newest 12 of 28 game versions. Older files are in the list below.
Check the dependencies, then try the file in a copied instance before changing a world you care about.
Recent files
Better Compatibility Checker versions and loaders
21.3.1
better-compatability-checker-fabric-21.3.1.jar
1 Jan 2026
Client Optional Server Optional Dependencies 1 unmatched of 2 Listed on Release listing
Check the 1.21.4 · Fabric setup 1.21.31.21.41.21.5Fabric release
Looking for an older file? The official Modrinth project page is in Resources.
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