Stack Size Modifier
by mert04c
Stack Size Modifier raises the maximum stack size of selected items, including Ender Pearls, potions, buckets and glass bottles, for Fabric on 1.21.7.
What it does
The mod is a lightweight Fabric addition that changes only the stack limit of chosen items. Throwable items such as Ender Pearls, drinkable, splash and lingering potions, and honey bottles can be stacked further than the vanilla default. Glass bottles, empty buckets, water, lava and milk buckets are covered as well, while most other items keep their usual limits. Players can carry more of these items in a single slot, which reduces how often inventories fill up during long trips or farming.
The change is meant to ease inventory management and leaves the rest of the game as it is: crafting, drops, brewing and bucket behavior stay unchanged. Items that normally stack to 64 keep their values unless the mod's settings name them. The mod runs on the client and the server, so both need it. Stack Size Modifier is available for Fabric only, with a single file for 1.21.7 dated 2026-02-03, and is released under the MIT License, but its code is not open source.
Key features
Higher ender pearl stacks
Ender Pearls can be stacked beyond the vanilla limit, so more pearls fit in one inventory slot.
Potions and honey bottles
Drinkable, splash and lingering potions, along with honey bottles, receive a larger stack size.
Buckets and glass bottles
Empty buckets, water, lava and milk buckets, and glass bottles are included in the stack size change.
Vanilla mechanics kept
Crafting, brewing and item behavior are not changed, so only the stack limit of the listed items differs.
Gallery
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Long expeditions
Players carrying many pearls, potions or buckets on a trip need fewer slots to hold the same supplies.
Potion brewing
Brewers who keep large numbers of bottles and potions in storage can fit more of them in each chest slot.
Who it’s for: Players and server owners who want larger stacks for a few specific items, without changing the rest of the game.
How it compares
PotionsButStackable is a Fabric mod for 1.21.11 that is client and server and is released under All rights reserved, so it is not open source. Stack 99 is a Fabric mod for 1.21.11 that is also client and server, under the GNU Lesser General Public License v3.0 or later, and is open source. Stackable Potions is a Fabric mod for 1.21.11, client and server, under the MIT License, and it is open source.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| Stack Size Modifier | Fabric | 1.21.7 | Client and server | 2026-02-03 |
| PotionsButStackable | Fabric | 1.21.11 | Client and server | 2026-05-31 |
| Stack 99 | Fabric | 1.21.11 | Client and server | 2026-02-21 |
| Stackable Potions | Fabric | 1.21.11 | Client and server | 2026-01-03 |
Questions
Does Stack Size Modifier require Fabric API?
Does the server need Stack Size Modifier?
Which game versions does the mod support?
In the catalog
Stack Size Modifier is one of 4,058 Storage mods on ModsFinder, and one of 2,474 Storage mods for Fabric. 13,697 mods support Minecraft 1.21.7.
More from mert04c
Similar mods
What the author says
Stack Size Modifier is a simple and lightweight Fabric mod that increases the maximum stack size of specific items to 64, improving inventory management without altering vanilla game mechanics. 🧪 Potions & Bottles (Default: 1) - Potion (Drinkable) - Splash Potion - Lingering Potion - Honey Bottle (Default: 16) …
Official listing
- Modrinth page
- modrinth.com/mod/stack-size-modifier
- Owner
- mert04c
- Published
- 2026-02-03
- Updated on Modrinth
- 2026-02-03
- Facts verified
- 2026-10-15