Light Level Overlay
Shows light levels on the surface of a block
About this Mod
LightLevelOverlay
Shows light levels on blocks. That is it. That is the mod.
Features
- Numbers on blocks so you can see exactly where mobs can spawn
- Color coded: Red (0), Yellow (1-7), Green (8+)
- Renders above foliage so you do not have to squint through grass
- Hides behind walls and only shows what you can actually see
- Fast, cached and optimized so it will not tank your FPS
- Underwater mode for drowned spawn prevention
Platforms
Works on both Fabric and NeoForge.
Controls
| Key | Action |
|---|---|
| F9 | Toggle overlay |
| F10 | Open config |
Config
Press F10 or edit config/lightleveloverlay-client.json
- Range: How far to scan (horizontal/vertical)
- Update Interval: Cache refresh rate in ms
- Colors: Customize the RGB values
- Show Only Spawnable: Hide safe blocks, show only danger zones
- Text Scale: Make numbers bigger or smaller
- Underwater Mode: Show light levels in water
Installation
- Install Fabric or NeoForge for Minecraft 1.21.1
- Install Architectury API for your loader
- Install Cloth Config for your loader
- Drop the jar in your mods folder
- Done
Dependencies
- Architectury API (required)
- Cloth Config (required)
- Fabric API (required for Fabric only)
Credits
Inspired by Light Level 2025 by dark-lion-jp. This is a standalone implementation, not a port, not affiliated. Bug reports go here, not there.
License
MIT
Available Versions
How to Install Light Level Overlay 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 (1.21.10).
Install Mod
Open the mod browser in the dashboard and search for "Light Level Overlay". Click "Install" – done! Alternatively, upload the .jar via SFTP to the /mods folder.
Compatibility
Mod Loaders
Minecraft Versions
1.21.10, 1.21.9, 1.21.8 (+6 more)
Server-side
✗ UnsupportedRecommended RAM
4 GB(min. 3 GB)Frequently Asked Questions
Light Level Overlay 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 (1.21.10). You can switch loaders with one click in the panel.
Is Light Level Overlay compatible with fabric and neoforge?
Light Level Overlay officially supports fabric, neoforge for Minecraft 1.21.10, 1.21.9, 1.21.8. The Mado dashboard automatically detects incompatible loader combinations.
Server lagging with Light Level Overlay – how to optimize performance?
Recommended RAM: 4 GB (per 8 players). Use /spark profiler to check if Light Level Overlay 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.
Similar Mods
Rent Modded Server
Install Light Level Overlay with just one click on your server.