Bob's Hotbar Optimizer
by z8ob_
With Bob's Hotbar Optimizer installed, switching to another hotbar slot takes effect without the usual one-tick wait.
What it does
Minecraft normally processes a slot change only on the next game tick, so a switch from slot 9 to slot 6 has to wait a tick before it is handled. The mod removes that delay, so the switch is applied as soon as the input is received. It is most noticeable in PvP and other fast-paced situations where a tick matters. The mod runs on the client alone, so players install it and servers do not need it. It is published for Fabric only, across 8 release versions 1.21.4 – 1.21.11, under the Apache License 2.0; the code is not open source.
Key features
No tick delay on slot switches
Slot changes are processed as soon as the input arrives, instead of waiting for the next tick.
Useful in combat
The shorter switching delay helps where a single tick can decide a fight, such as PvP.
Client-only install
Only the player's client needs the mod; a server can run without it.
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
How it compares
Tab Optimizer is a Fabric client mod for 1.21.11 under the MIT License and is open source. AppleHotbarOprimiser is a Fabric client mod for 1.21.4 – 1.21.11 that is not open source and is released under All rights reserved.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| Bob's Hotbar Optimizer | Fabric | 1.21.4 – 1.21.11 | Client-side only | 2026-02-09 |
| Tab Optimizer | Fabric | 1.21.11 | Client-side only | 2026-07-23 |
| AppleHotbarOprimiser | Fabric | 1.21.4 – 1.21.11 | Client-side only | 2026-08-02 |
Questions
Does Bob's Hotbar Optimizer need Fabric API?
Does the server need the mod?
In the catalog
Bob's Hotbar Optimizer is one of 3,545 Optimization mods on ModsFinder, and one of 2,575 Optimization mods for Fabric. 19,862 mods support Minecraft 1.21.11.
Similar mods
What the author says
Bob's Hotbar Optimizer removes the delay between switching hotbar slots that Minecraft has. This is done by making Minecraft process switching slots as soon as it receives the input. Normally, it waits until the next tick. Minecraft's slot processing works in a numerical order, from 1 - 9. If you're on slot 9, and…
Official listing
- Modrinth page
- modrinth.com/mod/bobs-hotbar-optimizer
- Owner
- z8ob_
- Published
- 2026-02-09
- Updated on Modrinth
- 2026-02-09
- Facts verified
- 2026-10-15