What do you need to install Minecraft mods?
You need Minecraft: Java Edition, a mod loader (Fabric, Forge or NeoForge) for your game version, and mods made for that same loader and version. Mods don't work in Bedrock Edition – consoles, phones and the Windows Bedrock version use add-ons from the Marketplace instead.
The three things must match:
| What | Example | Why it matters |
|---|---|---|
| Minecraft version | 1.21.1 | A mod is built for specific versions and won't load on others |
| Mod loader | NeoForge | A Fabric mod doesn't run on Forge or NeoForge, and the other way round |
| Mod file | create-1.21.1-….jar |
Download the file for your version and loader from the mod's page |
Which loader should you pick? The one your mods are made for. Every mod page on CurseForge and Modrinth lists its loaders and versions. As a rough guide: Fabric for performance and smaller mods (and quick updates to new versions), NeoForge for most big new mods on 1.21+, and Forge for older versions like 1.20.1, 1.16.5 or 1.12.2. The detailed comparison is in Forge vs NeoForge vs Fabric.
The easiest way: install mods with a launcher
Launchers such as the CurseForge App, Modrinth App or Prism Launcher install the mod loader for you and download mods with one click. If you're new to modding, start here – there's no folder to find and no installer to run.
CurseForge App
- Install the CurseForge App and choose Minecraft.
- Click Create Custom Profile, pick the Minecraft version and the loader (Fabric, Forge or NeoForge), and create it.
- Open the profile and click Add More Content (or browse mods), search for a mod and click Install. Required libraries are installed with it when the mod lists them.
- Click Play. The CurseForge App starts the official launcher with the right profile.
Modrinth App
- Install the Modrinth App and create a new instance with the + button: choose the loader and game version.
- Open the instance and add content – search for mods and click Install. The app only offers versions that match the instance.
- Click Play.
Prism Launcher
- Click Add Instance, choose the Minecraft version and pick a loader under Modloader.
- Select the instance, click Edit → Mods → Download mods, search and select the mods, then confirm.
- Launch the instance.
Each launcher profile has its own mods folder, worlds and settings, so you can keep a vanilla setup, a Fabric performance setup and a big modpack side by side without them breaking each other.
How to install mods manually (official launcher)
Run the loader's installer, start the game once with the new profile, then put the mod .jar files into the mods folder. This works with the official Minecraft launcher and doesn't need any extra app.
Step 1: Install the mod loader
| Loader | Where to get it | What to do |
|---|---|---|
| Fabric | fabricmc.net | Download the installer, choose Client, pick the Minecraft version and click Install |
| Forge | files.minecraftforge.net | Download the Installer for your version, run it and choose Install client |
| NeoForge | neoforged.net | Download the installer for your version, run it and choose Install client |
The installer adds a new profile to the official launcher, for example fabric-loader-… or forge-…. If the .jar installer doesn't open when you double-click it, your PC has no system Java – install a current Java version, or use one of the launchers above, which handle this for you.
Step 2: Start the game once
Open the official launcher, choose the new loader profile next to the Play button and start the game. The first start creates the mods folder. Close the game again.
Step 3: Put the mods in the mods folder
Copy the downloaded .jar files into the mods folder inside .minecraft – don't unzip them.
| System | Mods folder |
|---|---|
| Windows | %appdata%\.minecraft\mods (paste this into the Windows search or Run box) |
| macOS | ~/Library/Application Support/minecraft/mods |
| Linux | ~/.minecraft/mods |
On Fabric you almost always need Fabric API as well – most Fabric mods require it. Many other mods need library mods too, for example Architectury API or GeckoLib. The mod page lists them under dependencies or requirements; put them in the same folder.
Step 4: Start the game and check the mods
Start the game with the loader profile. On Forge and NeoForge the title screen has a Mods button that lists everything loaded. Fabric doesn't have one by default – add Mod Menu if you want the same list.
Only download mods from the mod's official page, CurseForge or Modrinth. Re-upload sites often bundle old versions, adware or worse – malware has been found in mod files spread outside trusted sites before.
How to install a Minecraft modpack
In the CurseForge App or Modrinth App, find the modpack, click Install and then Play – the launcher downloads the right loader, all the mods and the pack's settings. A modpack is simply a ready-made list of mods and configs that have been tested together.
- Open the CurseForge App (Minecraft → Browse modpacks) or the Modrinth App (Discover content → modpacks).
- Search for the pack and click Install. You can pick an older version of the pack if your server runs one.
- When the download finishes, click Play.
Big modpacks need more memory than the default 2 GB the official launcher gives Minecraft. If the game freezes on loading or crashes with an out-of-memory error, give it more RAM – how to do that in each launcher is in How to allocate more RAM to Minecraft. Not sure which pack to play? See Best Minecraft modpacks.
What are client-side and server-side mods?
Some mods only matter on your PC (client-side), some only on the server (server-side), and most content mods have to be on both. This matters as soon as you want to play mods with friends.
| Type | Examples | Install on |
|---|---|---|
| Both sides | New blocks, items, mobs, biomes, machines (e.g. Create) | The server and every player |
| Client-only | Shaders, minimaps, performance and graphics mods, UI tweaks | Only your own game |
| Server-only | Permissions, backups, server performance tools | Only the server |
Client-only mods are safe to add on your side even when the server doesn't have them. Mods that add content must be identical on both sides – same mods, same versions.
How to add mods to a Minecraft server
A modded server needs the same loader and Minecraft version as the players, plus every mod that adds content. The quickest way is a modpack: pick it when you create the server and the host installs everything.
On Spot.gg there are two ways:
- Modpack – choose one of over 1 300 modpacks from the modpack catalog when you create the server. The loader, mods and configs are installed for you, and the RAM is set to the pack's recommended amount. Your friends install the same pack (same version) in their launcher.
- Your own mods – create a server on Fabric, Forge or NeoForge for your Minecraft version. Then open "Addons" → "Available to install", search for a mod, choose the file marked "Compatible with your server" and click "Install". The panel offers a restart so the mod loads.
The panel doesn't show client-only mods, so you can't install something that would stop the server from starting. A mod that isn't in the catalog can be uploaded as a .jar to the mods folder in the "Files" tab or over SFTP. Already have a Vanilla or Paper server? Go to "Information" → "Modify" → "Change engine" to switch to a mod loader on the same Minecraft version – the world stays.
Modded servers on Spot.gg start at $7.55 per month, and you can try one free for 24 hours. The full step-by-step setup, including RAM sizes and how to fix a server that won't start, is in How to make a modded Minecraft server.
Why won't my mods work?
Almost every mod problem is a version mismatch, a missing dependency or two mods that don't get along. The game's crash screen or log usually names the mod.
| Problem | Likely cause | Fix |
|---|---|---|
| The mod doesn't show up in the Mods list | Wrong loader, or the game was started without the loader profile | Start with the Fabric/Forge/NeoForge profile; check the file is for that loader |
| Crash with a message about a missing mod | Missing dependency (e.g. Fabric API) | Install the mod named in the message |
| An error saying a mod needs a different Minecraft version | The mod is for a different Minecraft version | Download the file for your exact version |
| The game crashes with Exit Code 1 | A broken or conflicting mod, wrong Java or too little RAM | See Minecraft Exit Code 1 |
| Can't join a modded server ("incompatible FML modded server" or mismatched mod list) | Your mods or versions differ from the server's | Match the server's mod list exactly – see incompatible FML modded server |
| Game freezes while loading a big pack | Not enough RAM | Allocate more memory in your launcher |
When nothing helps, remove half of your mods and test again. If the problem is gone, it's in the half you removed – keep halving until you find the mod.
FAQ
How do I install mods in Minecraft?
Install a mod loader (Fabric, Forge or NeoForge) for your Minecraft version, start the game once with its profile, then put the mod .jar files into .minecraft/mods and start the game again. Launchers like the CurseForge App or Modrinth App do all of this for you.
Where is the Minecraft mods folder?
On Windows it is %appdata%\.minecraft\mods, on macOS ~/Library/Application Support/minecraft/mods and on Linux ~/.minecraft/mods. In third-party launchers each profile has its own mods folder.
Can you install mods on Minecraft Bedrock?
No. Mods for Fabric, Forge and NeoForge only work in Java Edition. Bedrock uses add-ons and Marketplace content instead.
Do I need Fabric API?
For most Fabric mods, yes. It's a library that many Fabric mods depend on. Put it in the same mods folder.
Can I use Fabric and Forge mods together?
Not in the same game. Pick one loader and use mods made for it. Some mods have builds for several loaders – download the right one.
How do I play mods with friends?
Everyone needs the same loader, Minecraft version and content mods. The easiest way is a modpack: the server runs it, and each friend installs the same pack and version in the CurseForge App or Modrinth App.
Are Minecraft mods safe?
Mods from CurseForge, Modrinth and the authors' official pages are generally safe. Avoid re-upload sites and unknown downloads, which can carry malware.