Stacknator

Stacknator

Properly configurable stack sizes for any vanilla or modded items

by
1.5K Downloads
fabricmanagementstorageutility
Rent Server with this Mod

About this Mod

Stacknator

Stacknator is a lightweight Minecraft mod for Fabric that lets you customize the maximum stack size of any vanilla or modded item via a simple configuration file. By modifying item data components during game initialization, Stacknator delivers a clean, efficient solution without performance overhead or hacky workarounds.

Compatibility

  • Required: Fabric API
  • Vanilla Items: Fully compatible.
  • Modded Items: Generally compatible with most mods.

Tags: Supported through the Filler feature.

Tip: To find an item's identifier, enable Advanced Tooltips in-game by pressing F3 + H, then hover over the item.

Installation

  1. Drop the Stacknator .jar into your mods folder.
  2. Start the server or load into a world.
  3. Edit the stacknator.json config file to set your desired stack sizes.
  4. Enjoy!

Required only on the server side for a survival gameplay, however it's recommended to have it on the client side as well to be fully compatible with some screens (e.g. creative screen).

Documentation

  • enabled:

    Enables or disables the mod.

    Type: boolean Default: true
  • log_modified_items:

    Toggles logging of successful stack size changes (other logs always show).

    Type: boolean Default: true
  • checks:

    Defines the checks to be performed.

    Type: object Default:
    • enable_checks:

      Enables or disables all checks.

      Type: boolean Default: true
    • check_damageable:

      Enables or disables the damageable check.

      Type: boolean Default: true
    • check_stackable:

      Enables or disables the stackable check.

      Type: boolean Default: false
    • check_minimum_stack_size:

      Enables or disables the minimum stack size check.

      Type: boolean Default: true
    • check_maximum_stack_size:

      Enables or disables the maximum stack size check.

      Type: boolean Default: true
  • remove_defaults:

    Removes all item entries that match the default stack size.

    Type: boolean Default: false
  • filler:

    Defines the filler settings.

    Type: object Default: {}
    • enable_filler:

      Enables or disables the filler. When enabled, the mod will iterate all registered items and apply the filler rules to each item while enforcing the configured checks.

      Type: boolean Default: false
    • reset_stacks:

      Enables or disables resetting of stack sizes to the default values, overriding any defined custom stack size.

      Type: boolean Default: false
    • run_once:

      Disables the filler after one run.

      Type: boolean Default: true
    • tag_priority:

      Enables or disables prioritizing tags over item entries when applying the filler.

      Type: boolean Default: true
    • tags:

      Defines tag identifiers and their custom stack sizes.

      Type: object Default: {}
  • sort_items:

    Enables or disabled sorting the item entries alphabetically by their keys.

    Type: boolean Default: true
  • items:

    Defines item identifiers and their custom stack sizes.

    Type: object Default: {}

Checks

Stacknator performs the following checks for each item/tag entry in the config file:

  • Entry Key Format:

    Verifies if the entry key follows the namespace:item format.

    On Failure: Skips the entry.
  • Item Damageable:

    Ensures the item is not damageable (e.g. tools, weapons and armor).

    On Failure: Skips the entry.
  • Item Stackable:

    Confirms the item is stackable (default maximum stack above 1).

    On Failure: Skips the entry.
  • Entry Value Below 1:

    Checks if the stack size is less than 1.

    On Failure: Skips the entry.
  • Entry Value Above 99:

    Checks if the stack size exceeds 99.

    On Failure: Adjusts to 99.

Full Configuration Example

{
  "enabled": true,
  "log_modified_items": true,
  "checks": {
    "enable_checks": true,
    "check_damageable": true,
    "check_stackable": false,
    "check_minimum_stack_size": true,
    "check_maximum_stack_size": true
  },
  "remove_defaults": false,
  "filler": {
    "enable_filler": false,
    "reset_stacks": false,
    "run_once": true,
    "tag_priority": true,
    "tags": {
        "#minecraft:logs": 16,
        "#minecraft:planks": 32
    }
  },
  "sort_items": true,
  "items": {
    "minecraft:egg": 64,
    "minecraft:red_bed": 16,
    "minecraft:ender_pearl": 32,
    "minecraft:tnt": 1
  }
}

Available Versions

Stacknator 2.0.0release
MC 26.1, 26.1.1, 26.1.2fabric
March 26, 2026
Stacknator 2.0.0release
MC 1.21.2, 1.21.3, 1.21.4, 1.21.5, 1.21.6, 1.21.7, 1.21.8, 1.21.9, 1.21.10, 1.21.11fabric
November 8, 2025
Stacknator 2.0.0release
MC 1.21, 1.21.1fabric
November 8, 2025
Stacknator 1.0.0release
MC 1.21.2, 1.21.3, 1.21.4, 1.21.5, 1.21.6, 1.21.7, 1.21.8fabric
September 21, 2025
Stacknator 1.0.0release
MC 1.21, 1.21.1fabric
September 21, 2025

How to Install Stacknator on Your Server

1

Order Server

Order a Minecraft Java server with at least 3 GB RAM (4 GB recommended).

2

Set fabric Loader

In the panel under "Egg", select the fabric loader and matching Minecraft version (26.1.2).

3

Install Mod

Open the mod browser in the dashboard and search for "Stacknator". Click "Install" – done! Alternatively, upload the .jar via SFTP to the /mods folder.

Compatibility

Mod Loaders

fabric

Minecraft Versions

26.1.2, 26.1.1, 26.1 (+12 more)

Server-side

Required

Recommended RAM

4 GB(min. 3 GB)

Frequently Asked Questions

Stacknator 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 (26.1.2). You can switch loaders with one click in the panel.

Is Stacknator compatible with fabric?

Stacknator officially supports fabric for Minecraft 26.1.2, 26.1.1, 26.1. The Mado dashboard automatically detects incompatible loader combinations.

Server lagging with Stacknator – how to optimize performance?

Recommended RAM: 4 GB (per 8 players). Use /spark profiler to check if Stacknator 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.

Rent Modded Server

Install Stacknator with just one click on your server.

Recommended RAM
4 GBab €8/mo
Min. 3 GB | +1 GB pro 8 Spieler
Create Server Now
1-Click Mod Install
NVMe SSD Storage
DDoS Protection included

Details

License
Apache License 2.0
Server-side
Required

Supported Versions

26.1.226.1.126.11.21.111.21.101.21.91.21.81.21.71.21.61.21.5+5 more