OutlineX
by HitBoost
OutlineX draws smooth, customizable outlines around blocks, so players can see which block they are aiming at more clearly.
What it does
OutlineX highlights the block under the crosshair with an outline that players can recolor. Each player can choose their own outline colors instead of the plain white border the game uses, and the settings are reached through a menu opened with the O key. The mod is written to stay light on performance, so it is meant to add little load to frame rates.
The mod suits builders, miners and PvP players who need to target and interact with blocks quickly. It runs on Fabric only and is published for 1.21 alone, with 1.0.0 for 1.21 as the latest file. Players need it installed, while a server may skip it. Its source code and issue tracker are public, and the license is Creative Commons Attribution Non Commercial No Derivatives 4.0, so the code is not open source.
Key features
Smooth block outlines
Outlines are drawn around the targeted block with smooth edges, aimed at reducing the visual glitches of plain borders.
Per-player colors
Each player sets outline colors on their own client, so the same server can show different colors to different people.
Settings menu
Pressing O opens the OutlineX menu, where the outline features are switched on or off and configured.
Lightweight rendering
The outline code is kept small and optimized to limit its effect on frame rate.
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Building and mining
Builders and miners can see the exact block they are targeting, which helps when placing or breaking blocks in tight spaces.
PvP and combat
Clear outlines on the targeted block make it easier to interact with blocks during fast fights.
Who it’s for: Builders, miners and PvP players who want a clearer block highlight on their own client. Players on servers that do not install the mod see nothing different.
How it compares
7msg Smooth Block Outline is a client-side only Fabric mod for 1.21.11 under All rights reserved, so it is not open source. Beautiful Hitboxes is client-side only for Fabric and covers 1.21.8 – 1.21.11. VexFPS is client-side only and released under the MIT License for 1.21.11. OutlineX is built for 1.21 alone, and its players need the mod while a server may skip it.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| OutlineX | Fabric | 1.21 | Client required, server optional | 2025-09-05 |
| 7msg Smooth Block Outline | Fabric | 1.21.11 | Client-side only | 2026-09-03 |
| Beautiful Hitboxes | Fabric | 1.21.8 – 1.21.11 | Client-side only | 2026-02-14 |
| VexFPS | Fabric | 1.21.11 | Client-side only | 2026-06-18 |
Questions
Does OutlineX need to be installed on the server?
Which loader does OutlineX use?
Can the outline colors be changed?
In the catalog
OutlineX is one of 3,545 Optimization mods on ModsFinder, and one of 2,575 Optimization mods for Fabric. 15,770 mods support Minecraft 1.21.
More from HitBoost
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What the author says
OutlineX is a modern Minecraft mod that enhances visibility by adding smooth, customizable outlines around blocks. Designed for builders, miners, and PvP players, it makes targeting and interacting with blocks more intuitive and visually clear. Instead of being stuck with plain white borders, OutlineX allows every…
Official listing
- Modrinth page
- modrinth.com/mod/outlinex
- Owner
- HitBoost
- Published
- 2025-09-05
- Updated on Modrinth
- 2025-09-05
- Facts verified
- 2026-10-15