ModsFinder

HitboxBackport

by Kwember

HitboxBackport brings the sneaking hitbox from later Minecraft releases to 1.12.2, letting players sneak under spaces such as top slabs.

ForgeClient and serverMIT LicenseOpen source1.12.2

What it does

The mod uses Mixins to change vanilla code so sneaking works like the newer hitbox, where the player can pass under gaps that are shorter than standing height. It also changes movement while swimming and crawling. Installing it needs a Mixin loader such as MixinBooter, and the mod is released under the MIT License, so the code is open source. It runs on client and server, so the server and every player need it, and files target 1.12.2 only.

Key features

  1. Sneaking under low gaps

    Players can crouch beneath spaces such as those under top slabs, as the newer sneaking hitbox allows.

  2. Crawling while sneaking

    The sneak change extends to crawling, so the player can move through low passages without standing.

  3. Swimming movement

    The hitbox change also alters how the player moves while swimming.

Compatibility

Latest build for each game version and loader.

1.12.21.0.3
ReleaseBetaAlphaNot available

Only full game releases are shown. This mod publishes no snapshot builds.

How it compares

Full comparison

Toggle Sneak & Sprint is client-side only, licensed under the Apache License 2.0, and works on 1.12.2 alone. Smooth Sneaking Mod is also client-side only and open source under the Apache License 2.0, with files for 1.8.8 – 1.12.2.

ModLoadersGame versionsEnvironmentUpdated
HitboxBackportForge1.12.2Client and server2025-02-18
Toggle Sneak & SprintForge1.12.2Client-side only2026-03-15
Smooth Sneaking ModForge1.8.8 – 1.12.2Client-side only2024-08-28

Questions

Does HitboxBackport need a Mixin loader?

Yes. The mod requires a Mixin loader such as MixinBooter, which must be installed alongside it on Forge 1.12.2.

Does the server need HitboxBackport?

Yes. Every player and the server need a copy of the mod.

In the catalog

HitboxBackport is one of 29,952 Game mechanics mods on ModsFinder, and one of 13,316 Game mechanics mods for Forge. 2,920 mods support Minecraft 1.12.2.

Game mechanics mods29,952Forge modsMods for 1.12.22,920

More from Kwember

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Curse Breaker1.12.2Musify!1.12.2SimpleNightmares1.12.2

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What the author says

The Minecraft 1.13 update included a change to the players hitbox when sneaking, allowing players to sneak under top slabs into 1.5 block tall spaces, this change was part a larger movement change for swimming, crawling and sneaking. This mod uses mixins to vanilla Minecraft's code to backport this change to sneaking…
Kwember, on the Modrinth page

Official listing

Owner
Kwember
Published
2025-02-18
Updated on Modrinth
2025-02-18
Facts verified
2026-10-15

Tags

Game mechanicsAdventureUtility
Open on ModrinthCompare