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

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

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

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
  }
}